Banana Squad hid data-stealing malware in fake GitHub repos posing as Python tools, tricking users and targeting sensitive info like browser and wallet data.

ReversingLabs researchers recently uncovered a new and worrying attack method led by a group called Banana Squad. This group, first identified by Checkmarx researchers in October 2023, is known for their sneaky methods, with their name coming from an early harmful internet address, bananasquadru.

ReversingLabs team, including Principal Malware Researcher Robert Simmons, found over 60 fake project folders, called repositories, on GitHub. These folders looked like real computer hacking tools written in Python, but they were actually trojanized, meaning they contained hidden malicious code.

Malicious code was placed in the top section of the repository, while the lower part appeared harmless (Image via ReversingLabs)

In their earlier attacks, starting in April 2023, Banana Squad put out hundreds of bad software packages under various usernames, researchers noted in their blog post shared with Hackread.com. These programs were designed for Windows computers and aimed to “steal extensive amounts of sensitive data,” including information from computers, apps, web browsers, and even cryptocurrency wallets by redirecting money.

These bad packages were downloaded nearly 75,000 times before they were found and removed. More recently, in November 2024, a harmful project from Banana Squad, found at dieserbenniru, showed a new trick. They used a GitHub feature where long lines of code don’t wrap.

Additionally, attackers added many spaces to push their malicious code off the screen, making it invisible to someone just looking at the code. This makes it much harder to spot the hidden danger. Fake user accounts, often with only one project listed, are commonly used by Banana Squad to host these harmful repositories.

Beyond Banana Squad’s specific activities, the overall increase in OSS risk points to ongoing problems. A new report for 2025 from ReversingLabs shows a changing picture in the safety of open-source software (OSS).

While overall malware found in OSS repositories significantly dropped in 2024 – a 70% decrease across platforms like npm, PyPI, and RubyGems compared to 2023 – the risk to software development from OSS is actually growing.

These threat actors are getting smarter. They are using more hidden and complex ways to attack, especially on platforms like GitHub, instead of just uploading simple malware. This positive trend in malware reduction is partly thanks to better security measures, including mandatory two-factor authentication (2FA) and the OpenSSF’s Malicious Packages Repository, launched in 2023.

Other reports indicate issues like a rise in secret leaks in 2024, where sensitive login details are exposed. Also, a look at top OSS packages revealed many security holes and code rot – a reliance on old, unmaintained code. This means popularity does not equate to security. The evolving threat means everyone using open-source software needs to be more watchful and use better tools to stay safe from groups like Banana Squad and other emerging threats.

Banana Squad Hides Data-Stealing Malware in Fake GitHub Repositories

North Korean hackers deploy PylangGhost malware through fake crypto job interviews targeting blockchain professionals with phishing and remote access tools.

A new series of cyber attacks is targeting professionals in the crypto and blockchain industries using fake recruitment scams, according to new research by Cisco Talos. The attackers, linked to a North Korea-aligned group known as Famous Chollima, are impersonating legitimate companies to trick victims into installing malware disguised as video drivers.

The group has been active since at least mid-2024, previously known for tactics like fake developer job postings and fraudulent interview processes. This latest development shows the operation evolving in sophistication, now with a new Python-based malware called PylangGhost, a variant of the previously identified GolangGhost trojan.

****Real Jobseekers, Fake Companies****

Victims are approached by fake recruiters offering positions at companies that appear to be in the crypto sector. Targets are often software developers, marketers and designers with cryptocurrency experience.

Once contact is made, the victim is directed to a fake skill-assessment page designed to look like it belongs to a real company, including well-known names like Coinbase, Robinhood, Uniswap and others.

These pages use the React framework and closely mimic real corporate interfaces. After filling out personal information and completing the test, applicants are told they must record a video introduction for the hiring team. To do so, they’re asked to install “video drivers” by copying and pasting commands into their terminal.

That step downloads the malware.

****How the Malware Works****

According to Cicso Talos’ blog post, if the victim follows instructions on a Windows or MacOS system, a malicious ZIP file is pulled down. It contains the Python-based PylangGhost trojan and related scripts. The malware then unpacks itself, runs in the background and gives attackers remote access to the victim’s machine.

Screenshot of MacOS instructions prompting the user to copy, paste and run a malicious command line script (Image via Cisco Talos)

The Python version functions almost identically to its Go-based counterpart. It installs itself to run every time the system starts, collects system info, and connects to a command and control server. Once active, it can receive and execute remote commands, harvest credentials, and steal browser data, including passwords and crypto wallet keys.

According to Talos, it targets more than 80 different browser extensions, including widely used password managers and digital wallets like MetaMask, 1Password, NordPass and Phantom.

The malware uses RC4 encryption for communication with its server. Though the data stream is encrypted, the encryption key is sent along with the data, limiting the security of that method. Still, the setup helps it blend in with regular traffic and makes detection harder.

The goal of this operation is twofold. First, it allows attackers to gather sensitive personal data from real jobseekers. Second, it opens the door for fake employees to be placed inside real companies, which could lead to long-term infiltration and access to valuable financial data or software infrastructure.

Only a small number of victims have been confirmed so far, mostly in India. Linux users are not affected in this particular campaign. No Cisco customers appear to have been impacted at this time.

Talos notes that the malware’s development does not seem to involve AI code generation, and the structure of both the Python and Go versions suggests the same developers created both.

****Stay Safe****

If you’re applying for roles in crypto or tech, be cautious with job listings that ask you to install software or run terminal commands as part of an interview. Legitimate companies will not require this.

Cybersecurity teams should review employee onboarding processes, especially for remote hires, and educate staff about these types of social engineering attacks. Monitoring for unexpected outbound connections or strange ZIP downloads can also help catch early signs of compromise.

N. Korean Hackers Use PylangGhost Malware in Fake Crypto Job Scam

In this edition, Thor shares how a week off with a new car turned into a crash course in modern vehicle tech. Surprisingly, it offers many parallels to cybersecurity usability.

Wednesday, June 18, 2025 14:00

Welcome to this week’s edition of the Threat Source newsletter. 

June 9 was Whit Monday — a bank holiday here in Germany — so I decided to take the whole week off. It turned out to be the perfect opportunity to try out a brand new car. Little did I know, I was about to get a crash course in modern vehicle technology (and a few unexpected life lessons).

There’s an EU regulation that requires new cars to come equipped with “Advanced Vehicle Systems,” which include features like driver drowsiness and attention warnings, lane-keeping systems and intelligent speed assistance. I hadn’t swapped cars in over a decade, so I was blissfully unaware of just how intrusive these systems could be. 

While I generally appreciate technology that makes our life safer, these features gave me a tough time. The car seemed to beep at me constantly, so much so that the beeping itself became a distraction. Instead of focusing on the road, I found myself trying to decipher what each alert meant. After a few kilometers, I had to pull over and consult the manual just to figure out how to disable these “helpful” assistants. 

Problem solved? Not quite. Every time I turned off and restarted the car, the systems re-enabled themselves. Disabling the lane-keeping assistant was just a button press, but turning off the “intelligent” speed assistant required a convoluted sequence: six menu clicks, a long press then a short click. I had to dig out the manual every time. 

You might think I’m just cutting corners, or that I should pay better attention to speed limits. But here’s the thing: Technology fails, and these systems are no exception. Sometimes the cameras miss speed signs, or worse, pick up the wrong ones. I’ve read about people putting stickers on their windshields to block the camera, only to discover the system then falls back to GPS data, which can be outdated or just plain wrong. On one occasion, it thought a car was on a 50 km/h road when the person was actually on the Autobahn directly next and parallel to the road, which famously has no speed limit. 

Some drivers try to muffle the alerts by gluing the speaker, but in modern cars, the system also lowers the radio volume to make sure you hear the alarm. Pulling the fuse would disable the emergency brake, too — not something I’m willing to risk, regardless of how insurance would feel about it.

I ended up learning two important lessons that week. The first was technical: I dove into the world of Controller Area Network (CAN) bus wiring, protocols, network gateways and tools like SavvyCAN to understand how these systems work... and maybe how to disable a few, purely for educational purposes. 

The second lesson hit me later, and it was more personal. In my job, I often preach about deploying multi-factor authentication (MFA) everywhere. My focus has always been on keeping out the bad guys, not on the user experience. I never understood why anyone would use apps to automatically accept authentication pushes — it seemed crazy to me. But after a a few days with the car, I finally saw things from the user’s perspective. Security tools can’t just be effective; they also have to be easy to use. Reducing friction, like using single sign-on or minimizing unnecessary clicks, matters just as much. Users also need to understand why these barriers are in place. 

Tomorrow is another holiday. Maybe I’ll spend it exploring Kali Linux 2025.2 and the latest CARsenal tools (formerly CAN Arsenal). Who knows? I might just tap a wire or two — for educational purposes only, of course.

**The one big thing **

Cisco Talos has discovered that the North Korean-aligned threat actor Famous Chollima has been actively targeting cryptocurrency and blockchain professionals (primarily in India) through sophisticated phishing campaigns. Previously known for using the GolangGhost trojan, they've now introduced a Python-based variant called PylangGhost, which retains the same capabilities. Recent campaigns have targeted Windows users with the Python version, while MacOS users are still being hit with the Golang-based variant.

**Why do I care? **

Even if you're not in the cryptocurrency or blockchain space, this campaign highlights how threat actors are constantly evolving their tools. It's a reminder that no matter how niche or localized an attack might seem, the techniques could easily be adapted to broader campaigns. Plus, if attackers succeed in these targeted efforts, stolen credentials could ripple across networks and platforms globally.

**So now what?**

Take this as your cue to double-check your defenses. Ensure your organization's security tools can detect Python and Golang-based malware, and educate your teams on recognizing phishing attempts, especially fake job offers. Stay proactive by monitoring emerging threats like PylangGhost, because even if you're not the target today, tomorrow isn’t a guarantee.

**Top security headlines of the week **

**AI Scraping Bots Are Breaking Open Libraries, Archives, and Museums**  
AI bots that scrape the internet for training data are hammering the servers of libraries, archives, museums and galleries, and are in some cases knocking their collections offline. (404 Media)

**Paraguay Suffered Data Breach: 7.4 Million Citizen Records Leaked on Dark Web**  
Hackers leaked the personal data of 7.4 million people in Paraguay on the dark web. A cybercriminal group called "Cyber PMC" demanded $7.4 million, blaming government corruption and poor security. (Security Affairs)

**Trend Micro fixes critical vulnerabilities in multiple products**  
Trend Micro has released security updates to address multiple critical-severity remote code execution and authentication bypass vulnerabilities. (Bleeping Computer)

**Can’t get enough Talos? **

**When legitimate tools go rogue**  
From LOLBins to open-source utilities like DonPAPI, threat actors are leveraging legitimate tools to evade detection and carry out attacks. Read the blog here.

**Microsoft Patch Tuesday for June 2025**   
Microsoft released its monthly security update last week, which includes 66 vulnerabilities affecting a range of products, including 10 that Microsoft marked as “critical.” Read the blog here.

**Upcoming events where you can find Talos **

*   REcon (June 27 – 29) Montreal, Canada 
*   NIRMA (July 28 – 30) St. Augustine, FL 
*   Black Hat USA (Aug. 2 – 7) Las Vegas, NV

**Most prevalent malware files from Talos telemetry over the past week **

**SHA 256: 9f1f11a708d393e0a4109ae189bc64f1f3e312653dcf317a2bd406f18ffcc507**  
MD5: 2915b3f8b703eb744fc54c81f4a9c67f  
VirusTotal: https://www.virustotal.com/gui/file/9f1f11a708d393e0a4109ae189bc64f1f3e312653dcf317a2bd406f18ffcc507  
Typical Filename: VID001.exe  
Claimed Product: N/A  
Detection Name: Win.Worm.Coinminer::1201

**SHA 256: a31f222fc283227f5e7988d1ad9c0aecd66d58bb7b4d8518ae23e110308dbf91**  
MD5: 7bdbd180c081fa63ca94f9c22c457376  
VirusTotal: https://www.virustotal.com/gui/file/a31f222fc283227f5e7988d1ad9c0aecd66d58bb7b4d8518ae23e110308dbf91/details    
Typical Filename: IMG001.exe  
Claimed Product: N/A  
Detection Name: Simple\_Custom\_Detection

A week with a "smart" car

An unidentified threat actor is using .lnk Windows shortcut files in a series of sophisticated attacks utilizing in-memory code execution and living-off-the-land cyberattack strategies.

Serpentine#Cloud Uses Cloudflare Tunnels in Sneak Attacks

Attackers are increasingly hiding in plain sight, using the same tools IT and security teams rely on for daily operations. This blog breaks down common techniques and provides recommendations to defenders.

Wednesday, June 18, 2025 06:09

Late one Tuesday night, Elena’s phone buzzed with an alert from her company’s SIEM. Her team had set up a rule to flag when certain system tools — whoami, nltest and nslookup—were run one after another in quick succession. That exact pattern had just triggered on a computer in the Finance Department. The time? 2:13 a.m.

Concerned, Elena logged in from home to investigate. Almost immediately, two more alerts appeared. One signaled that Mimikatz (a tool popular with threat actors to steal credentials) had been used on the same Finance machine. The other reported a PsExec download (a command line tool used to execute processes) on a domain controller.

Elena and her team began isolating systems and tracing the activity, determined to stop it before it spread any further. What first looked like routine system commands now clearly pointed to something more serious.

This story is a compartmentalized version of something we’re seeing more and more often in Cisco Talos Incident Response engagements: Rather than inventing their own tools, attackers are making use of familiar, legitimate software — just with a very different purpose. 

**What exactly are LOLBins?**

A big part of this trend revolves around “living off the land binaries,” or LOLBins. LOLBins are tools built into an operating system that attackers can use to carry out malicious actions without having to download or install any new software or utilities.

They’re especially concerning because they’re already installed, trusted, and frequently used for normal IT tasks, making them difficult to detect or block without disrupting operations.

Defenders can reference the “Living Off The Land Binaries, Scripts and Libraries” or LOLBAS project, which maintains a list of known LOLBins on GitHub.

**But it’s not just LOLBins…**

LOLBins were used often across Talos IR engagements in 2024, but we actually saw a wider variety of commercial and open-source tools used as well. Threat actors likely gravitate towards these because they can choose which tools best suit their needs best (or which commercial tools will blend into the victim environment). 

Take DonPAPI, for example. This is an open-source tool observed in several recent Talos IR engagements that automates credential dumping remotely on multiple Windows computers. It locates and retrieves Windows Data Protection API (DPAPI) protected credentials, a process also known as “DPAPI dumping.” DonPAPI searches for certain files, including Wi-Fi keys, RDP passwords and credentials saved in web browsers, to help authenticate and move laterally to identify other assets in the environment.

From an identity perspective, open-source tools like DonPAPI pose a significant risk to organizations based on their wide availability on code repositories like GitHub and their ease of installation. 

Here’s how this plays out in the field, using the top three examples of most used tools as observed in Cisco Talos’ 2024 Year in Review:

These tools weren’t built for attackers, but they’ve become some of the most common ingredients in ransomware and advanced persistent threat (APT) campaigns.

In a recent episode of The Talos Threat Perspective, one of our senior Talos IR consultants spoke about tools that were created for legitimate purposes (e.g., HRSword, REMCOS RAT and Cobalt Strike), but played a large part in the ransomware engagements investigated by Talos IR in 2025.

Lately, Talos has seen an increase in the use of remote monitoring and management (RMM) tools during attacks — the same kind of software IT teams and managed service providers rely on to access systems remotely. These tools are designed for legitimate use, but in the wrong hands, they become a stealthy way to maintain persistence on compromised systems without raising alarms.

One colleague shared a story that stuck with me: In some incidents, the attackers showed up with an entire toolkit of RMM software, testing each one to see which would slip through unnoticed (or not get blocked). Often, they’d use exactly the same tools already trusted by the target or their service provider, such as ScreenConnect or AnyDesk.

It’s like they arrived at the front door with a ring full of keys, trying each one until something clicked. And when the tool they use is something the environment already knows — already trusts — the question becomes: how do you spot the intruder when they’re using your own keys?

**How do you detect something that looks normal?**

Let’s go back to Elena. Her team stopped the attack not just because of the alert, but because they knew what should be running on that workstation. They had clear asset inventories and network behavior baselines, and they conducted continuous anomaly monitoring.

That’s really the heart of what works best when it comes to detecting these types of attacks:

*   Asset management: Know what’s installed and where. Know who owns what assets and what high-privileged accounts are for.
*   Behavioral baselining: Understand what “normal” looks like.
*   Continuous monitoring: Configure detections to catch known TTPs and subtle deviations from baselines.
*   Threat intel alignment: Use current trends like the DonPAPI surge to inform what you log and watch for. Talos’ blog and IR reports are great resources to keep up with industry trends.

**Bottom line**

Whether it’s PsExec, DonPAPI or TeamViewer, attackers are increasingly hiding in plain sight, using the same tools IT and security teams rely on for daily operations.

Detecting malicious use of legitimate tools isn’t just about recognizing what’s running. It’s about asking why it’s running.

Sometimes, the only difference between a routine operation and a breach is the analyst who stopped to ask: “Why was that tool running at 2:13 a.m.?”

When legitimate tools go rogue

Learn how the North Korean-aligned Famous Chollima is using the a new Python-based RAT, "PylangGhost," to target cryptocurrency and blockchain jobseekers in a campaign affecting users primarily in India.

Wednesday, June 18, 2025 06:00

*   In May 2025, Cisco Talos identified a Python-based remote access trojan (RAT) we call “PylangGhost,” used exclusively by a North Korean-aligned threat actor. PylangGhost is functionally similar to the previously documented GolangGhost RAT, sharing many of the same capabilities. 
*   In recent campaigns, the threat actor Famous Chollima — potentially made up of multiple groups — has been using a Python-based version of their trojan to target Windows systems, while continuing to deploy a Golang-based version for MacOS users. Linux users are not targeted in these latest campaigns. 
*   The attacks are targeting employees with experience in cryptocurrency and blockchain technologies. 
*   Based on open-source intelligence, only a small number of users, predominantly in India, are affected. Cisco product telemetry does not indicate that there are any affected Cisco users. 

Since mid-2024, the threat actor group Famous Chollima (aka Wagemole), a North Korean-aligned threat actor, has been very active through several well-documented campaigns. These campaigns include using variants of Contagious Interview (aka DeceptiveDevelopment) and creating fake job advertisements and skill-testing pages. In the latter, users are instructed to copy and paste (ClickFix) a malicious command line in order to install drivers necessary to conduct the final skill-testing stage.  

Toward the end of the year, researchers documented Famous Chollima’s remote access trojan (RAT) called “GolangGhost” in its source code format, which was frequently used as the final payload in the threat actor’s ClickFix campaigns. 

In May 2025, Cisco Talos discovered threat actors starting to deploy a functionally equivalent Python variant of GolangGhost trojan, which we call “PylangGhost.” 

**Fake job interview sites mislead users to PylangGhost infection **

Famous Chollima seek financial benefit using a two-pronged approach: first, by creating fake employers for the purpose of jobseekers exposing their personal information, and second by deploying fake employees as workers in targeted victim companies.  

This blog focuses on the first method, where real software engineers, marketing employees, designers and other workers are targeted by fake recruiters and instructed to visit skill-testing pages in order to move forward with their application. 

Based on the advertised positions, it is clear that the Famous Chollima is broadly targeting individuals with previous experience in cryptocurrency and blockchain technologies. The skill-testing sites attempt to impersonate real companies such as Coinbase, Archblock, Robinhood, Parallel Studios, Uniswap and others, which helps with the targeting.  

Figure 1. Examples of initial fake job sites.

Each target is sent an invite code to visit a testing website where, depending on the position, they are instructed to enter their details and answer several questions to test their experience and skills. The sites are created using the React framework and have very similar visual designs, no matter the type of position.  

__Figure 2. Example of questions asked for an illegitimate Business Development Manager position at Robinhood.__

Once the user answers all the questions and provides personal details, the site displays an invitation to record a video for the interviewer, recommending that the user request camera access by pressing a button. 

__Figure 3. A camera setup page displayed once questions are answered.__

Finally, when the user requests camera, the site displays the instructions for the user to copy, paste and execute a command to allegedly install the required video drivers, if the OS is supported. When Talos used Windows and MacOS test systems, the instructions were shown as seen in Figure 4 and 5. The Linux test system led to another error message, without any instructions to download and install the payload.  

Figure 4. Windows instructions to copy, paste and execute a malicious command. 

Figure 5. MacOS instructions to copy, paste and execute a malicious command. 

Instructions for downloading the alleged fix are different based on the browser fingerprinting, and also given in appropriate shell language for the OS: PowerShell or Command Shell for Windows, and Bash for MacOS.

__Figure 6. Command Shell, PowerShell or Bash instructions to download a payload.__

**PylangGhost - Python variant of GolangGhost **

As the Golang variant of the RAT is already well-documented, this blog focuses on the Python version and the similarities between the two. The initial stage consists of a command line which the fake webpage tells the unsuspecting user to copy, paste and execute. 

The command line uses either PowerShell Invoke-Webrequest or curl to download a ZIP file containing the PylangGhost modules as well as Visual Basic Script file. This script is responsible for unzipping the Python library stored in the “lib.zip file” and launching the trojan by running a renamed Python interpreter using the file “nvidia.py” as the Python program to run. 

Figure 7. The first stage simply unzips a Python distribution library and launches the RAT. 

 PylangGhost consists of six well-structured Python modules. It is not clear to Talos why the threat actors decided to create two variants using a different programming language, or which was created first. Based on the comments in the code, it is unlikely that the threat actors used a large language model (LLM) to help rewrite the code for Python. One of the strings in the configuration module file (“config.py”) indicates that the Python version is 1.0, while the appropriate configuration variable in the Golang version indicates that the version is 2.0. However, Talos cannot definitively conclude that those two version numbers are comparable. 

 The execution starts with the file “nvidia.py”, which performs several tasks: It creates a registry value to launch the RAT every time user logs onto the system, generates a GUID for the system to be used in communication with command and control (C2) server, connects to the C2 server and enters the command loop for communication with the server.  

__Figure 8. ”nvidia.py” executes the main loop for communication with the C2 server__

 The configuration file “config.py” specifies the commands that can be received from the server, which are identical to the commands previously documented in the Golang version of the RAT. These commands enable remote control the infected system and the theft of cookies and credentials from over 80 browser extensions, including password managers and cryptocurrency wallets, including Metamask, 1Password, NordPass, Phantom, Bitski, Initia, TronLink and MultiverseX. 

The command handling module, “command.py”, defines function handlers and handles the commands received from the C2 server.  

Command 

Functionality 

qwer 

COMMAND\_INFORMATION - collect information about the infected system, username, OS version etc 

asdf 

COMMAND\_FILE\_UPLOAD - file upload 

zxcv 

COMMAND\_FILE\_DOWNLOAD - file download 

vbcx 

COMMAND\_OS\_SHELL - launch an OS shell for remote access and control of the infected system 

ghdj 

COMMAND\_WAIT - sleep for a number of seconds specified by the C2 server 

r4ys 

COMMAND\_AUTO - browser information stealing command 

89io 

AUTO\_CHROME\_GATHER\_COMMAND - subcommand of the browser information stealer command 

gi%# 

AUTO\_CHROME\_COOKIE\_COMMAND - subcommand of the browser information stealer command 

dghh 

COMMAND\_EXIT 

_Table 1. Commands and functionalities._

The module “auto.py” contains the functionality for stealing the stored browser credentials and session cookies, as well as collecting data from various browser extensions.  

“Api.py” is responsible for implementing the communications protocol with the C2 server, using RC4 encryption to encrypt packets over otherwise unencrypted HTTP used while communicating with the C2 server. The data in a HTTP packet is encrypted with RC4 algorithm, but the encryption key is also sent within the packet structure. The packet begins with 16 bytes of MD5 checksum for the rest of the packet, for verification of data integrity, followed by 128 bytes containing the RC4 encryption key, followed by an encrypted data blob.  

Finally, “util.py” handles the compression and decompression of files. 

**Comparison of Python and Golang modules **

To assess the similarity between the two versions, Talos compares the names of the modules written in different languages as well as their functionality. The structure, the naming conventions and the function names are very similar, which indicates that the developers of the different versions either worked closely together or are the same person.   

Module 

Python name 

Golang name 

Main function module 

nvidia.py 

cloudfixer.go 

Configuration module 

config.py 

config/constans.go 

Main command loop 

nvidia.py 

core/loop.go 

Command handlers 

command.py 

core/loop.go 

Browser Stealer functionality 

auto.py 

auto/\* modules 

File compression 

util.py 

util/compress.go 

Base64 message encoding 

command.py 

command/stackcmd.go 

Duplicate process check 

nvidia.py 

instance/check.go 

Communications protocol 

api.py 

transport/htxp.go 

_Table 2. Comparison of Python and Golang RAT module names._ 

**Coverage  **

Ways our customers can detect and block this threat are listed below.  

Cisco Secure Endpoint (formerly AMP for Endpoints) is ideally suited to prevent the execution of the malware detailed in this post. Try Secure Endpoint for free here.  

Cisco Secure Email (formerly Cisco Email Security) can block malicious emails sent by threat actors as part of their campaign. You can try Secure Email for free here.  

Cisco Secure Firewall (formerly Next-Generation Firewall and Firepower NGFW) appliances such as Threat Defense Virtual, Adaptive Security Appliance and Meraki MX can detect malicious activity associated with this threat.  

Cisco Secure Network/Cloud Analytics (Stealthwatch/Stealthwatch Cloud) analyzes network traffic automatically and alerts users of potentially unwanted activity on every connected device.  

Cisco Secure Malware Analytics (Threat Grid) identifies malicious binaries and builds protection into all Cisco Secure products.  

Cisco Secure Access is a modern cloud-delivered Security Service Edge (SSE) built on Zero Trust principles.  Secure Access provides seamless transparent and secure access to the internet, cloud services or private application no matter where your users work.  Please contact your Cisco account representative or authorized partner if you are interested in a free trial of Cisco Secure Access.  

Umbrella, Cisco’s secure internet gateway (SIG), blocks users from connecting to malicious domains, IPs and URLs, whether users are on or off the corporate network.   

Cisco Secure Web Appliance (formerly Web Security Appliance) automatically blocks potentially dangerous sites and tests suspicious sites before users access them.   

Additional protections with context to your specific environment and threat data are available from the Firewall Management Center.  

Cisco Duo provides multi-factor authentication for users to ensure only those authorized are accessing your network.   

Open-source Snort Subscriber Rule Set customers can stay up to date by downloading the latest rule pack available for purchase on Snort.org.  

ClamAV detections available for this threat:

Win.Backdoor.PyChollima-10045389-0
Win.Backdoor.PyChollima-10045388-0
Win.Backdoor.PyChollima-10045387-0
Win.Backdoor.PyChollima-10045386-0
Win.Backdoor.PyChollima-10045385-0
Win.Backdoor.PyChollima-10045384-0

**IOCs **

The IOCs can also be found in our GitHub repository here.

**SHA256 **

a206ea9b415a0eafd731b4eec762a5b5e8df8d9007e93046029d83316989790a - auto.py  
c2137cd870de0af6662f56c97d27b86004f47b866ab27190a97bde7518a9ac1b - auto.py  
0d14960395a9d396d413c2160570116e835f8b3200033a0e4e150f5e50b68bec - api.py 
8ead05bb10e6ab0627fcb3dd5baa59cdaab79aa3522a38dad0b7f1bc0dada10a - api.py 
5273d68b3aef1f5ebf420b91d66a064e34c4d3495332fd492fecb7ef4b19624e - nvidia.py 
267009d555f59e9bf5d82be8a046427f04a16d15c63d9c7ecca749b11d8c8fc3 - nvidia.py 
7ac3ffb78ae1d2d9b5d3d336d2a2409bd8f2f15f5fb371a1337dd487bd471e32 - nvidia.py 
b7ab674c5ce421d9233577806343fc95602ba5385aa4624b42ebd3af6e97d3e5 - util.py 
fb5362c4540a3cbff8cb1c678c00cc39801dc38151edc4a953e66ade3e069225 - util.py 
d029be4142fca334af8fe0f5f467a0e0e1c89d3b881833ee53c1e804dc912cfd - command.py 
b8402db19371db55eebea08cf1c1af984c3786d03ff7eae954de98a5c1186cee - command.py 
1f482ce7e736a8541cc16e3e80c7890d13fb1f561ae38215a98a75dce1333cee - config.py 
ed170975e3fd03440360628f447110e016f176a44f951fcf6bc8cdb47fbd8e0e - config.py 
929c69827cd2b03e7b03f9a53c08268ab37c29ac4bd1b23425f66a62ad74a13b - config.py 
127406b838228c39b368faa9d6903e7e712105b5ad8f43a987a99f7b10c29780 - config.py 
0ec9d355f482a292990055a9074fdabdb75d72630b920a61bdf387f2826f5385 - update.vbs 
c2d2320ae43aaa0798cbcec163a0265cba511f8d42d90d45cd49a43fe1c40be6 - update.vbs 
e7c2b524f5cb0761a973accc9a4163294d678f5ce6aca73a94d4e106f4c8fea4 - nvidiaRelease.zip 
28198494f0ed5033085615a57573e3d748af19e4bd6ea215893ebeacf6e576df - vdriverWin.zip 
fc71a1df2bb4ac2a1cc3f306c3bdf0d754b9fab6d1ac78e4eceba5c6e7aee85d - nvidiaRelease.zip 
d3500266325555c9e777a4c585afc05dfd73b4cbe9dba741c5876593b78059fd - nvidiaRelease.zip 

**C2 servers **

hxxp\[://\]31\[.\]57\[.\]243\[.\]29:8080 
hxxp\[://\]154\[.\]58\[.\]204\[.\]15:8080 
hxxp\[://\]212\[.\]81\[.\]47\[.\]217:8080 
hxxp\[://\] 31\[.\]57\[.\]243\[.\]190:8080

**Download host names **

api\[.\]quickcamfix\[.\]online   
api\[.\]auto-fixer\[.\]online   
api\[.\]quickdriverupdate\[.\]online   
api\[.\]camtuneup\[.\]online   
api\[.\]driversofthub\[.\]online   
api\[.\]drive-release\[.\]cloud   
api\[.\]vcamfixer\[.\]online   
api\[.\]nvidia-drive\[.\]cloud   
api\[.\]nvidia-release\[.\]us   
api\[.\]autodriverfix\[.\]online   
api\[.\]camdriversupport\[.\]com   
api\[.\]smartdriverfix\[.\]cloud   
api\[.\]drivercams\[.\]cloud   
api\[.\]camtechdrivers\[.\]com   
api\[.\]web-cam\[.\]cloud   
api\[.\]camera-drive\[.\]org   
api\[.\]nvidia-release\[.\]org 
api\[.\]fixdiskpro\[.\]online 
api\[.\]autocamfixer\[.\]online

**Fake job interview host names **

krakenhire\[.\]com  
yuga\[.\]skillquestions\[.\]com  
uniswap\[.\]speakure\[.\]com  
doodles\[.\]skillquestions\[.\]com  
www\[.\]hireviavideo\[.\]com  
kraken\[.\]livehiringpro\[.\]com  
quiz-nest\[.\]com  
www\[.\]smartvideohire\[.\]com  
www\[.\]talent-hiringstep\[.\]com  
provevidskillcheck\[.\]com  
skill\[.\]vidintermaster\[.\]com  
digitaltalent\[.\]review  
robinhood\[.\]ecareerscan\[.\]com  
evalswift\[.\]com  
livetalentpro\[.\]com  
quantumnodespro\[.\]com  
evalassesso\[.\]com  
parallel\[.\]eskillora\[.\]com  
coinbase\[.\]talentmonitoringtool\[.\]com  
uniswap\[.\]testforhire\[.\]com  
coinbase\[.\]talenthiringtool\[.\]com  
crosstheages\[.\]skillence360\[.\]com 
parallel \[.\] eskillprov \[.\] com 
assesstrack \[.\] com 
coinbase \[.\] talentmonitoringtool \[.\] com 
talent-hiringtalk\[.\]com 
uniswap\[.\]prehireiq\[.\]com 
fast-video-recording\[.\]com

Famous Chollima deploying Python version of GolangGhost RAT

Late last year, security researchers made a startling discovery: Kremlin-backed disinformation campaigns were bypassing moderation on social media platforms by leveraging the same malicious advertising technology that powers a sprawling ecosystem of online hucksters and website hackers. A new report on the fallout from that investigation finds this dark ad tech industry is far more resilient and incestuous than previously known.

Late last year, security researchers made a startling discovery: Kremlin-backed disinformation campaigns were bypassing moderation on social media platforms by leveraging the same malicious advertising technology that powers a sprawling ecosystem of online hucksters and website hackers. A new report on the fallout from that investigation finds this dark ad tech industry is far more resilient and incestuous than previously known.

Image: Infoblox.

In November 2024, researchers at the security firm **Qurium** published an investigation into “Doppelganger,” a disinformation network that promotes pro-Russian narratives and infiltrates Europe’s media landscape by pushing fake news through a network of cloned websites.

Doppelganger campaigns use specialized links that bounce the visitor’s browser through a long series of domains before the fake news content is served. Qurium found Doppelganger relies on a sophisticated “domain cloaking” service, a technology that allows websites to present different content to search engines compared to what regular visitors see. The use of cloaking services helps the disinformation sites remain online longer than they otherwise would, while ensuring that only the targeted audience gets to view the intended content.

Qurium discovered that Doppelganger’s cloaking service also promoted online dating sites, and shared much of the same infrastructure with **VexTrio**, which is thought to be the oldest malicious traffic distribution system (TDS) in existence. While TDSs are commonly used by legitimate advertising networks to manage traffic from disparate sources and to track who or what is behind each click, VexTrio’s TDS largely manages web traffic from victims of phishing, malware, and social engineering scams.

**BREAKING BAD**

Digging deeper, Qurium noticed Doppelganger’s cloaking service used an Internet provider in Switzerland as the first entry point in a chain of domain redirections. They also noticed the same infrastructure hosted a pair of co-branded affiliate marketing services that were driving traffic to sketchy adult dating sites: **LosPollos\[.\]com** and **TacoLoco\[.\]co**.

The LosPollos ad network incorporates many elements and references from the hit series “Breaking Bad,” mirroring the fictional “Los Pollos Hermanos” restaurant chain that served as a money laundering operation for a violent methamphetamine cartel.

The LosPollos advertising network invokes characters and themes from the hit show Breaking Bad. The logo for LosPollos (upper left) is the image of Gustavo Fring, the fictional chicken restaurant chain owner in the show.

Affiliates who sign up with LosPollos are given JavaScript-heavy “**smartlinks**” that drive traffic into the VexTrio TDS, which in turn distributes the traffic among a variety of advertising partners, including dating services, sweepstakes offers, bait-and-switch mobile apps, financial scams and malware download sites.

LosPollos affiliates typically stitch these smart links into **WordPress** websites that have been hacked via known vulnerabilities, and those affiliates will earn a small commission each time an Internet user referred by any of their hacked sites falls for one of these lures.

The Los Pollos advertising network promoting itself on LinkedIn.

According to Qurium, TacoLoco is a traffic monetization network that uses deceptive tactics to trick Internet users into enabling “push notifications,” a cross-platform browser standard that allows websites to show pop-up messages which appear outside of the browser. For example, on Microsoft Windows systems these notifications typically show up in the bottom right corner of the screen — just above the system clock.

In the case of VexTrio and TacoLoco, the notification approval requests themselves are deceptive — disguised as “CAPTCHA” challenges designed to distinguish automated bot traffic from real visitors. For years, VexTrio and its partners have successfully tricked countless users into enabling these site notifications, which are then used to continuously pepper the victim’s device with a variety of phony virus alerts and misleading pop-up messages.

Examples of VexTrio landing pages that lead users to accept push notifications on their device.

According to a December 2024 annual report from **GoDaddy**, _nearly 40 percent of compromised websites in 2024 redirected visitors to VexTrio via LosPollos smartlinks_.

**ADSPRO AND TEKNOLOGY**

On November 14, 2024, Qurium published research to support its findings that LosPollos and TacoLoco were services operated by **Adspro Group**, a company registered in the Czech Republic and Russia, and that Adspro runs its infrastructure at the Swiss hosting providers **C41** and **Teknology SA**.

Qurium noted the LosPollos and TacoLoco sites state that their content is copyrighted by **ByteCore AG** and **SkyForge Digital AG**, both Swiss firms that are run by the owner of Teknology SA, **Giulio Vitorrio Leonardo Cerutti**. Further investigation revealed LosPollos and TacoLoco were apps developed by a company called **Holacode**, which lists Cerutti as its CEO.

The apps marketed by Holacode include numerous VPN services, as well as one called **Spamshield** that claims to stop unwanted push notifications. But in January, Infoblox said they tested the app on their own mobile devices, and found it hides the user’s notifications, and then after 24 hours stops hiding them and demands payment. Spamshield subsequently changed its developer name from Holacode to **ApLabz**, although Infoblox noted that the Terms of Service for several of the rebranded ApLabz apps still referenced Holacode in their terms of service.

Incredibly, Cerutti threatened to sue me for defamation before I’d even uttered his name or sent him a request for comment (Cerutti sent the unsolicited legal threat back in January after his company and my name were merely tagged in an Infoblox post on LinkedIn about VexTrio).

Asked to comment on the findings by Qurium and Infoblox, Cerutti vehemently denied being associated with VexTrio. Cerutti asserted that his companies all strictly adhere to the regulations of the countries in which they operate, and that they have been completely transparent about all of their operations.

“We are a group operating in the advertising and marketing space, with an affiliate network program,” Cerutti responded. “I am not \[going\] to say we are perfect, but I strongly declare we have no connection with VexTrio at all.”

“Unfortunately, as a big player in this space we also get to deal with plenty of publisher fraud, sketchy traffic, fake clicks, bots, hacked, listed and resold publisher accounts, etc, etc.,” Cerutti continued. “We bleed lots of money to such malpractices and conduct regular internal screenings and audits in a constant battle to remove bad traffic sources. It is also a highly competitive space, where some upstarts will often play dirty against more established mainstream players like us.”

Working with Qurium, researchers at the security firm **Infoblox** released details about VexTrio’s infrastructure to their industry partners. Just four days after Qurium published its findings, LosPollos announced it was suspending its push monetization service. Less than a month later, Adspro had rebranded to **Aimed Global**.

A mind map illustrating some of the key findings and connections in the Infoblox and Qurium investigations. Click to enlarge.

**A REVEALING PIVOT**

In March 2025, researchers at GoDaddy chronicled how **DollyWay** — a malware strain that has consistently redirected victims to VexTrio throughout its eight years of activity — suddenly stopped doing that on November 20, 2024. Virtually overnight, DollyWay and several other malware families that had previously used VexTrio began pushing their traffic through another TDS called **Help TDS**.

Digging further into historical DNS records and the unique code scripts used by the Help TDS, Infoblox determined it has long enjoyed an exclusive relationship with VexTrio (at least until LosPollos ended its push monetization service in November).

In a report released today, Infoblox said an exhaustive analysis of the JavaScript code, website lures, smartlinks and DNS patterns used by VexTrio and Help TDS linked them with at least four other TDS operators (not counting TacoLoco). Those four entities — **Partners House**, **BroPush**, **RichAds** and **RexPush** — are all Russia-based push monetization programs that pay affiliates to drive signups for a variety of schemes, but mostly online dating services.

“As Los Pollos push monetization ended, we’ve seen an increase in fake CAPTCHAs that drive user acceptance of push notifications, particularly from Partners House,” the Infoblox report reads. “The relationship of these commercial entities remains a mystery; while they are certainly long-time partners redirecting traffic to one another, and they all have a Russian nexus, there is no overt common ownership.”

**Renee Burton**, vice president of threat intelligence at Infoblox, said the security industry generally treats the deceptive methods used by VexTrio and other malicious TDSs as a kind of legally grey area that is mostly associated with less dangerous security threats, such as adware and scareware.

But Burton argues that this view is myopic, and helps perpetuate a dark adtech industry that also pushes plenty of straight-up malware, noting that hundreds of thousands of compromised websites around the world every year redirect victims to the tangled web of VexTrio and VexTrio-affiliate TDSs.

“These TDSs are a nefarious threat, because they’re the ones you can connect to the delivery of things like information stealers and scams that cost consumers billions of dollars a year,” Burton said. “From a larger strategic perspective, my takeaway is that Russian organized crime has control of malicious adtech, and these are just some of the many groups involved.”

**WHAT CAN YOU DO?**

As KrebsOnSecurity warned way back in 2020, it’s a good idea to be very sparing in approving notifications when browsing the Web. In many cases these notifications are benign, but as we’ve seen there are numerous dodgy firms that are paying site owners to install their notification scripts, and then reselling that communications pathway to scammers and online hucksters.

If you’d like to prevent sites from ever presenting notification requests, all of the major browser makers let you do this — either across the board or on a per-website basis. While it is true that blocking notifications entirely can break the functionality of some websites, doing this for any devices you manage on behalf of your less tech-savvy friends or family members might end up saving everyone a lot of headache down the road.

To modify site notification settings in **Mozilla Firefox**, navigate to Settings, Privacy & Security, Permissions, and click the “Settings” tab next to “Notifications.” That page will display any notifications already permitted and allow you to edit or delete any entries. Tick the box next to “Block new requests asking to allow notifications” to stop them altogether.

In **Google Chrome**, click the icon with the three dots to the right of the address bar, scroll all the way down to Settings, Privacy and Security, Site Settings, and Notifications. Select the “Don’t allow sites to send notifications” button if you want to banish notification requests forever.

In Apple’s **Safari** browser, go to Settings, Websites, and click on Notifications in the sidebar. Uncheck the option to “allow websites to ask for permission to send notifications” if you wish to turn off notification requests entirely.

Inside a Dark Adtech Empire Fed by Fake CAPTCHAs

Cisco Talos’ Vulnerability Discovery & Research team recently disclosed three zero-day vulnerabilities in catdoc, as well as vulnerabilities in Parallel, NVIDIA and High-Logic FontCreator 15.

Wednesday, June 11, 2025 09:47

Cisco Talos’ Vulnerability Discovery & Research team recently disclosed three zero-day vulnerabilities in catdoc, as well as vulnerabilities in Parallel, NVIDIA and High-Logic FontCreator 15. 

The vulnerabilities mentioned in this blog post have been patched by their respective vendors, in adherence to Cisco’s third-party vulnerability disclosure policy, except in the case of the catdoc zero-day vulnerabilities, which were patched by our researcher (patches found in this repository). This is an unusual case, because the vendor could not be reached to fix these high-risk bugs; our policy does not include fixing third-party vulnerabilities. 

For Snort coverage that can detect the exploitation of these vulnerabilities, download the latest rule sets from Snort.org, and our latest Vulnerability Advisories are always posted on Talos Intelligence’s website.      

**catdoc zero-day vulnerabilities **

_Discovered by Ali Rizvi-Santiago of Cisco Talos._    

The catdoc program pulls plain text content from Microsoft Word, Excel, PowerPoint and Rich Text Format files. The vendor was unreachable, Debian will be merging our patches into their distribution. https://github.com/Cisco-Talos/catdoc-talos-fixes/releases/tag/talos-fixes.2025-05

TALOS-2024-2128 (CVE-2024-48877) is a memory corruption vulnerability in the Shared String Table Record Parser implementation in xls2csv utility version 0.95. A specially crafted malformed file can lead to a heap buffer overflow. An attacker can provide a malicious file to trigger this vulnerability. 

TALOS-2024-2131 (CVE-2024-52035) is an integer overflow vulnerability which exists in the OLE Document File Allocation Table Parser functionality of catdoc 0.95., and TALOS-2024-2132 (CVE-2024-54028) is an integer underflow vulnerability in the OLE Document DIFAT Parser functionality. A specially crafted malformed file can lead to heap-based memory corruption for either vulnerability, and an attacker can provide a malicious file as a trigger. 

**Parallel integer overflow vulnerability  **

_Discovered by KPC of Cisco Talos._    

Parallels is a desktop emulator for Mac computers that enables virtual Windows applications.

TALOS-2025-2160 (CVE-2025-31359) is a directory traversal vulnerability exists in the PVMP package unpacking functionality of Parallels Desktop for Mac version 20.2.2 (55879). This vulnerability can be exploited by an attacker to write to arbitrary files, potentially leading to privilege escalation.

There are three privilege escalation vulnerabilities in the virtual machine archive restoration functionality of Parallels Desktop for Mac version 20.1.1 (55740).

*   TALOS-2024-2126 (CVE-2024-36486): When an archived virtual machine is restored, the prl\_vmarchiver tool decompresses the file and writes the content back to its original location using root privileges. An attacker can exploit this process by using a hard link to write to an arbitrary file, potentially resulting in privilege escalation.
*   TALOS-2024-2124 (CVE-2024-54189): When a snapshot of a virtual machine is taken, a root service writes to a file owned by a normal user. By using a hard link, an attacker can write to an arbitrary file, potentially leading to privilege escalation.
*   TALOS-2024-2123 (CVE-2024-52561): When a snapshot of a virtual machine is deleted, a root service verifies and modifies the ownership of the snapshot files. By using a symlink, an attacker can change the ownership of files owned by root to a lower-privilege user, potentially leading to privilege escalation.

**NVIDIA integer overflow vulnerability  **

_Discovered by Dimitrios Tatsis of Cisco Talos._    

NVIDIA cuobjdump is a command-line utility included in the NVIDIA CUDA Toolkit. Similar to the standard \`objdump\` utility, it parses CUDA executable files and displays information like PTX disassembly, section headers, relocations etc. 

TALOS-2025-2151 (CVE-2025-23247) is an integer overflow in the ELF Section Parsing functionality of NVIDIA cuobjdump 12.8.55. A specially crafted fatbin file can lead to an out-of-bounds write. An attacker can provide a malicious file to trigger this vulnerability. 

**High-Logic out-of-bounds read vulnerability  **

_Discovered by KPC of Cisco Talos._    

High-Logic FontCreator is a font editor for Windows & macOS. The program allows you to create, edit and export OpenType, TrueType and responsive variable fonts. 

An out-of-bounds read vulnerability, TALOS-2025-2157 (CVE-2025-20001), exists in High-Logic FontCreator 15.0.0.3015. A specially crafted font file can trigger this vulnerability which can lead to disclosure of sensitive information. An attacker needs to trick the user into opening the malicious file to trigger this vulnerability.

catdoc zero-day, NVIDIA, High-Logic FontCreator and Parallel vulnerabilities

Microsoft today released security updates to fix at least 67 vulnerabilities in its Windows operating systems and software. Redmond warns that one of the flaws is already under active attack, and that software blueprints showing how to exploit a pervasive Windows bug patched this month are now public.

**Microsoft** today released security updates to fix at least 67 vulnerabilities in its **Windows** operating systems and software. Redmond warns that one of the flaws is already under active attack, and that software blueprints showing how to exploit a pervasive Windows bug patched this month are now public.

The sole zero-day flaw this month is CVE-2025-33053, a remote code execution flaw in the Windows implementation of **WebDAV** — an HTTP extension that lets users remotely manage files and directories on a server. While WebDAV isn’t enabled by default in Windows, its presence in legacy or specialized systems still makes it a relevant target, said **Seth Hoyt**, senior security engineer at **Automox**.

**Adam Barnett**, lead software engineer at **Rapid7**, said Microsoft’s advisory for CVE-2025-33053 does not mention that the Windows implementation of WebDAV is listed as deprecated since November 2023, which in practical terms means that the WebClient service no longer starts by default.

“The advisory also has attack complexity as low, which means that exploitation does not require preparation of the target environment in any way that is beyond the attacker’s control,” Barnett said. “Exploitation relies on the user clicking a malicious link. It’s not clear how an asset would be immediately vulnerable if the service isn’t running, but all versions of Windows receive a patch, including those released since the deprecation of WebClient, like Server 2025 and Windows 11 24H2.”

Microsoft warns that an “elevation of privilege” vulnerability in the **Windows Server Message Block** (SMB) client (CVE-2025-33073) is likely to be exploited, given that proof-of-concept code for this bug is now public. CVE-2025-33073 has a CVSS risk score of 8.8 (out of 10), and exploitation of the flaw leads to the attacker gaining “SYSTEM” level control over a vulnerable PC.

“What makes this especially dangerous is that no further user interaction is required after the initial connection—something attackers can often trigger without the user realizing it,” said **Alex Vovk**, co-founder and CEO of **Action1**. “Given the high privilege level and ease of exploitation, this flaw poses a significant risk to Windows environments. The scope of affected systems is extensive, as SMB is a core Windows protocol used for file and printer sharing and inter-process communication.”

Beyond these highlights, 10 of the vulnerabilities fixed this month were rated “critical” by Microsoft, including eight remote code execution flaws.

Notably absent from this month’s patch batch is a fix for a newly discovered weakness in **Windows Server 2025** that allows attackers to act with the privileges of any user in Active Directory. The bug, dubbed “**BadSuccessor**,” was publicly disclosed by researchers at **Akamai** on May 21, and several public proof-of-concepts are now available. Tenable’s Satnam Narang said organizations that have at least one Windows Server 2025 domain controller should review permissions for principals and limit those permissions as much as possible.

**Adobe** has released updates for **Acrobat Reader** and six other products addressing at least 259 vulnerabilities, most of them in an update for **Experience Manager**. **Mozilla Firefox** and **Google Chrome** both recently released security updates that require a restart of the browser to take effect. The latest Chrome update fixes two zero-day exploits in the browser (CVE-2025-5419 and CVE-2025-4664).

For a detailed breakdown on the individual security updates released by Microsoft today, check out the Patch Tuesday roundup from the **SANS Internet Storm Center**. Action 1 has a breakdown of patches from Microsoft and a raft of other software vendors releasing fixes this month. As always, please back up your system and/or data before patching, and feel free to drop a note in the comments if you run into any problems applying these updates.

Patch Tuesday, June 2025 Edition

June 2025 Patch Tuesday fixes 66 bugs, including a zero-day in WebDAV. Update Windows, Office, and more now to block active threats.

Microsoft’s June Patch Tuesday update has landed, bringing security fixes for 66 vulnerabilities across its product line. Among the patched flaws is one that was already being exploited in real-world attacks, making this month’s updates particularly important for both enterprises and individual users.

****One Zero-Day Actively Exploited****

The standout fix addresses CVE-2025-33053, a vulnerability in the WebDAV component of Windows. This flaw could allow attackers to execute code remotely if exploited correctly. Since it was already being used in attacks before today’s patch release, it falls into the “zero-day” category.

The WebDAV vulnerability affects both Windows 10 and Windows 11, along with related server versions. While Microsoft has not disclosed the full details of the attacks, they have confirmed that the bug was found in use in the wild.

****10 Critical Issues Fixed****

In addition to the zero-day, Microsoft patched 10 vulnerabilities rated Critical, which generally means they allow remote code execution or elevation of privilege without much user interaction. These include four bugs in Microsoft Office, which continue to be a regular target for attackers looking to send malicious documents through email.

Other products receiving fixes include Microsoft Edge, Power Automate, .NET, and components of Windows itself. While none of the other issues were reported as actively exploited, several are marked as more likely to be targeted in the near term.

****Windows Update Details****

The updated packages are available now and include:

*   **Windows 11**: KB5060842 (22H2 and 23H2)

*   **Windows 10**: KB5060533 and KB5060999

*   **Windows Server versions**: Also updated, depending on the build in use.

Admins should check their update management systems to confirm rollout and assess any compatibility concerns that may arise from the latest patches.

****Why This Month Matters****

The quick exploitation of CVE-2025-33053 once again shows how fast attackers move when new vulnerabilities are disclosed. While zero days often make headlines, the other fixes should not be ignored. Several of this month’s bugs involve components often exposed to the internet or frequently used in enterprise environments.

Companies that delay patching are not just risking data theft but also the cost of recovery from ransomware, which often begins with bugs like the ones patched today.

Nick Carroll, cyber incident response manager at Nightwing, the intelligence solutions company divested from RTX, commented on the Patch Tuesday event, stating, _“_There are a couple of vulnerabilities for the Windows Common Log File System (CVE-2025-32701 and CVE-2025-32706) which are Priv Esc vulnerabilities. Those aren’t critical, which means some organizations won’t prioritize patching them as quickly as they probably should. And if you look at what tends to get a lot of attention, critical vulnerabilities catch all the buzz,” noted Nick.

_“_But we see real world attacks abusing that Windows Log File subsystem pretty regularly. In fact, Nightwing has defended against exploits in the Windows Common Log File System in real world attacks last month related to the recently patched CVE-2025-29824 where the threat actors were abusing Living-off-the-Land tactics in conjunction with the exploit,” he added.

****What to Do Now****

*   **Apply all available June updates as soon as possible**, especially for systems using WebDAV

*   **Review your Office file handling policies**, especially if users frequently receive documents from outside the organization

*   **Monitor network traffic** for signs of suspicious activity linked to WebDAV or other patched services

*   **Test in staging environments** before rolling out company-wide, especially in environments with older or customized software stacks

Microsoft’s full advisory can be found on its official security update guide. Patching quickly remains one of the simplest and most effective defences against many forms of cyberattacks.

Tag

#windows