Plus, new details emerge on the Scattered Spider cybercrime network and ArcaneDoor.

Thursday, April 25, 2024 14:00

I wrote last week about the problems arising from the massive backlog of vulnerabilities at the U.S. National Vulnerability Database.  

Thousands of CVEs are still without analysis data, and the once-reliable database of every single vulnerability that’s disclosed and/or patched is now so far behind, it could take up to 100 days for the National Institute of Standards and Technology (NIST) to catch up, and that would be assuming no new vulnerabilities are disclosed during that period. 

While the U.S. government and NIST try to sort out a potential solution, and hopefully await more funding and restructuring, NIST says it’s hoping to launch a consortium to help either rebuild the NVD or create a replacement.  

Other security experts have floated the idea of other companies or organizations creating a brand-new solution of their own. The main problem with that is, what’s in it for them?  

What works about the NVD is that it’s funded by the U.S. government, so the money is always coming in to help fund the workforce and at least gives MITRE and the other private companies who contribute to the NVD motivation to keep working on it. 

To start up a whole new database of \*every\* CVE out there would take countless man-hours, and then what at the end? Would the company or person(s) who created it start charging for access? 

Several open-source solutions have_man-hours_ popped up over the past few weeks, such as “NVD Data Overrides,” which “is meant to provide additional data that is currently missing from NVD.” However, these types of volunteer projects still can’t assign CVSS scores, because only the NVD is authorized to hand out official NVD CVSS scores. 

This brings up another problem for private companies that may want to develop a solution: Do they want to play referee?  

Sometimes, when there’s a disagreement on how severe a vulnerability is and what severity score to assign it, the NVD will weigh in and provide their own, independently calculated CVSS score. Who really wants to be the “bad guy” to get between a massive tech company like Microsoft or Apple and a security researcher saying a vulnerability is a 9.5 out of 10 CVSS? 

I absolutely give major credit to any volunteers or open-source developers who are working on their own solutions for essentially nothing — but how long can we expect them to keep maintaining these databases? 

Unfortunately, I don’t have a great answer for this, either. I’m far from an expert on vulnerability management, nor do I have any connections to the federal government. But I do feel the onus is on the government to come up with a solution, and potentially provide incentives for companies and researchers to participate in this new proposed consortium because I don’t see the incentives there for the private sector to come up with their own solution.  

**The one big thing **

ArcaneDoor is a new campaign that is the latest example of state-sponsored actors targeting perimeter network devices from multiple vendors. Talos and Cisco PSIRT recently identified a previously unknown actor, now tracked as UAT4356 by Talos and STORM-1849 by the Microsoft Threat Intelligence Center. This actor utilized bespoke tooling that demonstrated a clear focus on espionage and an in-depth knowledge of the devices that they targeted, hallmarks of a sophisticated state-sponsored actor. UAT4356 deployed two backdoors as components of this campaign, “Line Runner” and “Line Dancer,” which were used collectively to conduct malicious actions on-target, which included configuration modification, reconnaissance, network traffic capture/exfiltration and potentially lateral movement.   

**Why do I care? **

Gaining a foothold on these devices allows an actor to directly pivot into an organization, reroute or modify traffic and monitor network communications. In the past two years, we have seen a dramatic and sustained increase in the targeting of these devices in areas such as telecommunications providers and energy sector organizations — critical infrastructure entities that are likely strategic targets of interest for many foreign governments. As a critical path for data into and out of the network, these devices need to be routinely and promptly patched; using up-to-date hardware and software versions and configurations; and be closely monitored from a security perspective. 

**So now what? **

There are some known indicators of compromise that customers can look for if they suspect they may have been targeted in this campaign. First, organizations should look for any flows to/from ASA devices to any of the IP addresses present in the IOC list provided at the bottom of this blog. This is one indication that further investigation is necessary. Potential targets can also follow the steps detailed in the Cisco ASA Forensic Investigation Procedures for First Responders. When following these procedures, first responders should NOT attempt to collect a core dump or reboot the device if they believe that the device has been compromised, based on the lina memory region output. Talos also released some Snort signatures to detect the activity on the wire including access attempts. Snort Signatures 63139, 62949 and 45575 have been released to detect the implants or associated behaviors. 

**Top security headlines of the week **

**A previously known Windows print spooler bug is still being actively exploited, according to Microsoft.** The company’s threat research team recently disclosed that APT28, a well-known Russian state-sponsored actor, is exploiting the vulnerability to deliver a previously unknown malware called “GooseEgg.” Microsoft disclosed and patched CVE-2022-38028 in October 2022, but APT28 may have been exploiting it as far back as 2020. The actor’s exploitation involved modifying a JavaScript constraints file in the printer spooler and executing it with SYSTEM-level permissions. The new research prompted the U.S. Cybersecurity and Infrastructure Security Agency (CISA) to add CVE-2022-38028 to its Known Exploited Vulnerabilities (KEV) catalog. If installed, GooseEgg can load other applications with System-level permissions and allow the adversary to execute remote code on the targeted device or deploy other backdoors. Another set of print spooler vulnerabilities, called PrintNightmare, made headlines in July 2021, though no one reported active exploitation of that vulnerability at the time. (SC Magazine, Security Week) 

**A new investigation revealed how members of the group Scattered Spider are partnering with Russian state-sponsored actors to carry out ransomware attacks.** Scattered Spider is made up of younger individuals based out of the U.S., U.K. and Canada. They are primarily English speakers who have been blamed for several notable ransomware attacks, including one against MGM Casinos that disrupted operations at several casinos and hotels last year. The group specializes in social engineering, more recently using LinkedIn to steal employee information and use that to infiltrate corporate networks. Members, some as young as teenagers, are connecting over the dark web and online forums like Discord and use their advanced knowledge of Western civilization to provide crucial details to Russian actors. The “60 Minutes” investigation also included new details about The Community (aka “The Comm,” the online collection of hackers who like to brag about their recent cybercrimes, often through Telegram. (CBS News) 

**The U.S. government has re-upped a law that expands government surveillance by opening the door for private companies to partner with the government on these types of activities.** The controversial Foreign Intelligence Surveillance Act (FISA) was re-approved just hours after it lapsed. The White House and proponents in U.S. Congress argued that the powers granted in Section 702 of the FISA helps prevent the spread of terrorism and cyber attacks and that any lapse in those powers would harm the government’s ability to gather crucial intelligence. However, privacy advocates say that the FISA is an overreach, and provides too much power for private companies to potentially spy on consumers. The bill also includes a new definition of “electronic communications service provider,” which could allow the U.S. government to force Big Tech companies and telecommunications providers to hand over users’ data if requested. (NBC News, TechCrunch) 

**Can’t get enough Talos? **

*   Talos Takes Ep. #180: What are the dangers of enabling sideloading and third-party apps? 
*   Suspected CoralRaider continues to expand victimology using three information stealers 
*   Brute-force attacks surge worldwide, warns Cisco Talos    
*   Cisco Warns of Massive Surge in Password-Spraying Attacks on VPNs 
*   Rare Computer Virus Detected in Ukrainian Network, Confidential Document Potentially Compromised 

**Upcoming events where you can find Talos **

**CARO Workshop 2024** **(May 1 - 3)** 

_Arlington, Virginia_

> Over the past year, we’ve observed a substantial uptick in attacks by YoroTrooper, a relatively nascent espionage-oriented threat actor operating against the Commonwealth of Independent Countries (CIS) since at least 2022. Asheer Malhotra's presentation at CARO 2024 will provide an overview of their various campaigns detailing the commodity and custom-built malware employed by the actor, their discovery and evolution in tactics. He will present a timeline of successful intrusions carried out by YoroTrooper targeting high-value individuals associated with CIS government agencies over the last two years.

**RSA** **(May 6 - 9)** 

_San Francisco, California_    

**Cisco Live** **(June 2 - 6)** 

_Las Vegas, Nevada_  

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

_This section will be on a brief hiatus while we work through some technical difficulties._ _Several open-source solutions have_

The private sector probably isn’t coming to save the NVD

Attacks by a previously unknown threat actor leveraged two bugs in firewall devices to install custom backdoors on several government networks globally.

Source: Znakki via Shutterstock

A state-sponsored threat actor has exploited two Cisco zero-day vulnerabilities in firewall devices to target the perimeter of government networks with two custom-built backdoors, in a global cyber-espionage campaign.

Dubbed "ArcaneDoor," the campaign by the previously unknown actor — which researchers from Cisco Talos track as UAT4356 — has targeted Cisco Adaptive Security Appliance (ASA) firewall devices of several Cisco customers since at least December 2023, Cisco Talos researchers revealed in a blog post.

While the actor's initial access vector remains unknown, once it occurs, UAT4356 used a "sophisticated attack chain" involving exploit of the two vulnerabilities — a denial-of-service flaw tracked as CVE-2024-20353 and a persistent local execution flaw tracked as CVE-2024-20359 that have since been patched — to implant malware and execute commands across a small set of Cisco customers. Cisco Talos also flagged a third flaw in ASA, CVE-2024-20358, that was not used in the ArcaneDoor campaign.

The researchers also found evidence that the actor has interest in and potentially will attack devices from Microsoft and other vendors, making it crucial that organizations ensure that all perimeter devices "are properly patched, logging to a central, secure location, and configured to have strong multifactor authentication (MFA)," Cisco Talos wrote in the post.

**Custom Backdoor Malware for Global Governments**

The first sign of suspicious activity in the campaign came in early 2024 when a customer reached out to Cisco's Product Security Incident Response Team (PSIRT) and Cisco Talos about security concerns with its ASA firewall devices.

A subsequent several-months-long investigation conducted by Cisco and intelligence partners uncovered threat actor-controlled infrastructure dating back to early November 2023. Most of the attacks — all of which targeted government networks globally —occurred between December and early January. There is also evidence that the actor — which Microsoft also is now tracking as STORM-1849 — was testing and developing its capability as early as last July.

The primary payloads of the campaign are two custom backdoors— "Line Dancer" and "Line Runner" — which were used together by UAT4356 to conduct malicious activities on the network, such as configuration and modification; reconnaissance; network traffic capture/exfiltration; and potentially lateral movement.  

Line Dancer is a memory-resident shellcode interpreter that enables adversaries to upload and execute arbitrary shellcode payloads. In the campaign, Cisco Talos observed the malware being used to execute various commands on an ASA device, including: disabling the syslog; running and exfiltrating the command show configuration; creating and exfiltrating packet captures; and executing commands present in the shellcode, among other activities.

Line Runner meanwhile is a persistence mechanism deployed on the ASA device using functionality related to a legacy capability that allowed for the pre-loading of VPN clients and plugins on the device during booting that can be exploited as CVE-2024-20359, according to Cisco Talos. In at least one case, the threat actor also abused CVE-2024-20353 to facilitate this process.

"The attackers were able to leverage this vulnerability to cause the target ASA device to reboot, triggering the unzipping and installing" of Line Runner, according to the researchers.

**Protect the Perimeter From Cyberattackers**

Perimeter devices, which sit at the edge between an organization's internal network and the Internet, "are the perfect intrusion point for espionage-focused campaigns," providing threat actors a way to gain a foothold to "directly pivot into an organization, reroute or modify traffic, and monitor network communications into the secure network, according to Cisco Talos.

Zero-days on these devices are an especially attractive attack surface on these devices, notes Andrew Costis, chapter lead of the Adversary Research Team at MITRE ATT&CK testing firm AttackIQ.

"We've seen time and time again critical zero and n-day vulnerabilities being exploited with all of the mainstream security appliances and software," he says, noting previous attacks on bugs in devices from Ivanti, Palo Alto Networks, and others.

The threat to these devices highlights the need for organizations to "routinely and promptly" patch them using up-to-date hardware and software versions and configurations, as well as maintain close security monitoring of them, according to Cisco Talos.

Organizations also should focus on post-compromise TTPs of threat actors and test known adversary behaviors as part of "a layered approach" to defensive network operations, Costis says.

**Detecting ArcaneDoor Cyberattack Activity**

Indicators of compromise (IoCs) that customers can look for if they suspect they may have been targeted by ArcaneDoor include any flows to/from ASA devices to any of the IP addresses present in the IOC list included in the blog.

Organizations also can issue the command "show memory region | include lina" to identify another IOC. "If the output indicates more than one executable memory region … especially if one of these memory sections is exactly 0x1000 bytes, then this is a sign of potential tampering," Cisco Talos wrote.  

And, Cisco provided two sets of steps that network administrators can take to identify and remove the ArcaneDoor persistence backdoor Line Runner on an ASA device once the patch is applied. The first is to conduct a review of the contents of disk0; if a new file (e.g., "client\_bundle\_install.zip" or any other unusual .zip file) appears on the disk, it means that Line Runner had been present but is no longer active due to the update.

Administrators also can follow a series of commands provided that will create an innocuous file with a .zip extension that will be read by the ASA at reboot. If it appears on disk0, it means that Line Runner likely was present on the device in question. Administrators can then delete the "client\_bundle\_install.zip" file to remove the backdoor.

If administrators find a newly created .zip file on their ASA devices, they should copy that file off the device and email \[email protected\] using a reference to CVE-2024-20359 and including the outputs of the "dir disk0:" and "show version" commands from the device, as well as the .zip file that they extracted.

**About the Author(s)**

Elizabeth Montalbano is a freelance writer, journalist, and therapeutic writing mentor with more than 25 years of professional experience. Her areas of expertise include technology, business, and culture. Elizabeth previously lived and worked as a full-time journalist in Phoenix, San Francisco, and New York City; she currently resides in a village on the southwest coast of Portugal. In her free time, she enjoys surfing, hiking with her dogs, traveling, playing music, yoga, and cooking.

Cisco Zero-Days Anchor 'ArcaneDoor' Cyber-Espionage Campaign

Unlike the SolarWinds and CodeCov incidents, all that it took for an adversary to nearly pull off a massive supply chain attack was some slick social engineering and a string of pressure emails.

Source: Mongta Studio via Shutterstock

An adversary doesn't need sophisticated technical skills to execute a broad software supply chain attack like the ones experienced by SolarWinds and CodeCov. Sometimes, all it takes is a little bit of time and ingenius social engineering.

That appears to have been the case with whoever introduced a backdoor in the XZ Utils open source data compression utility in Linux systems earlier this year. Analysis of the incident from Kaspersky this week, and similar reports from others in recent days, identified the attacker as relying almost entirely on social manipulation to slip the backdoor into the utility.

**Social Engineering the Open Source Software Supply Chain**

Ominously, it may be a model that attackers are using to slip similar malware into other widely used open source projects and components.

In an alert last week, the Open Source Security Foundation (OSSF) warned of the XZ Utils attack likely not being an isolated incident. The advisory identified at least one other instance where an adversary employed tactics similar to the one used on XZ Utils to take over the OpenJS Foundation for JavaScript projects.

"The OSSF and OpenJS Foundations are calling all open source maintainers to be alert for social engineering takeover attempts, to recognize the early threat patterns emerging, and to take steps to protect their open source projects," the OSSF alert said.

A developer from Microsoft discovered the backdoor in newer versions of an XZ library called liblzma while investigating odd behavior around a Debian installation. At the time, only unstable and beta releases of Fedora, Debian, Kali, openSUSE, and Arch Linux versions had the backdoored library, meaning it was virtually a non-issue for most Linux users.

But the manner in which the attacker introduced the backdoor is especially troubling, Kasperksy said. "One of the key differentiators of the SolarWinds incident from prior supply chain attacks was the adversary’s covert, prolonged access to the source/development environment," Kaspersky said. "In this XZ Utils incident, this prolonged access was obtained via social engineering and extended with fictitious human identity interactions in plain sight."

**A Low and Slow Attack**

The attack appears to have begun in October 2021, when an individual using the handle "Jia Tan" submitted an innocuous patch to the single-person XZ Utils project. Over the next few weeks and months, the Jia Tan account submitted multiple similar harmless patches (described in detail in this timeline) to the XZ Utils project, which its sole maintainer, an individual named Lasse Collins, eventually began merging into the utility.

Starting in April 2022, a couple of other personas — one using the handle "Jigar Kumar" and the other "Dennis Ens" — began sending emails to Collins, pressuring him to integrate Tan's patches into XZ Utils at a faster pace.

The Jigar Kumar and Dennis Ens personas gradually ratcheted up the pressure on Collins, eventually asking him to add another maintainer to the project. Collins at one point reaffirmed his interest in maintaining the project but confessed to being constrained by "long-term mental health issues." Eventually, Collins succumbed to the pressure from Kumar and Ens and gave Jia Tan commit access to the project and the authority to make changes to the code.

"Their goal was to grant full access to XZ Utils source code to Jia Tan and subtly introduce malicious code into XZ Utils," Kaspersky said. "The identities even interact with one another on mail threads, complaining about the need to replace Lasse Collin as the XZ Utils maintainer." The different personas in the attack — Jia Tan, Jigar Kumar, and Dennis Ens — appear to have deliberately been made to look like they were from different geographies, to dispel any doubts about their working in concert. Another individual, or persona, Hans Jansen, surfaced briefly in June 2023 with some new performance optimization code for XZ Utils that ended up being integrated into the utility.

**A Wide Cast of Actors**

Jia Tan introduced the backdoor binary into the utility in February 2024 after gaining control of the XZ Util maintenance tasks. Following that, the Jansen character resurfaced — along with two other personas — each pressuring major Linux distributors to introduce the backdoored utility into their distribution, Kasperksy said.

What's not entirely clear is if the attack involved a small team of actors or a single individual who successfully managed several identities and manipulated the maintainer into giving them the right to make code changes to the project.

Kurt Baumgartner, principal researcher at Kaspersky’s global research and analysis team, tells Dark Reading that additional data sources, including login and netflow data, could help aid in the investigation of the identities involved in the attack. "The world of open source is a wildly open one," he says, "enabling murky identities to contribute questionable code to projects that are major dependencies."

**About the Author(s)**

Jai Vijayan is a seasoned technology reporter with over 20 years of experience in IT trade journalism. He was most recently a Senior Editor at Computerworld, where he covered information security and data privacy issues for the publication. Over the course of his 20-year career at Computerworld, Jai also covered a variety of other technology topics, including big data, Hadoop, Internet of Things, e-voting, and data analytics. Prior to Computerworld, Jai covered technology issues for The Economic Times in Bangalore, India. Jai has a Master's degree in Statistics and lives in Naperville, Ill.

Attacker Social-Engineered Backdoor Code Into XZ Utils

ArcaneDoor is a campaign that is the latest example of state-sponsored actors targeting perimeter network devices from multiple vendors. Coveted by these actors, perimeter network devices are the perfect intrusion point for espionage-focused campaigns.

ArcaneDoor - New espionage-focused campaign found targeting perimeter network devices

A new malware campaign has been exploiting the updating mechanism of the eScan antivirus software to distribute backdoors and cryptocurrency miners like XMRig through a long-standing threat codenamed GuptiMiner targeting large corporate networks.
Cybersecurity firm Avast said the activity is the work of a threat actor with possible connections to a North Korean hacking group dubbed

eScan Antivirus Update Mechanism Exploited to Spread Backdoors and Miners

Growing attacks targeting the flaw prompted CISA to include it in the known exploited vulnerabilities catalog earlier this month.

Source: HJBC via Shutterstock

Siemens is urging organizations using its Ruggedcom APE1808 devices configured with Palo Alto Networks (PAN) Virtual NGFW to implement workarounds for a maximum severity zero-day bug that PAN recently disclosed in its next-gen firewall product.

The command injection vulnerability, identified as CVE-2024-3400, affects multiple versions of PAN-OS firewalls when certain features are enabled on them. An attacker has been exploiting the flaw to deploy a novel Python backdoor on affected firewalls.

**Actively Exploited**

PAN patched the flaw after researchers from Volexity discovered the vulnerability and reported it to the security vendor earlier this month. The US Cybersecurity and Infrastructure Security Agency (CISA) added CVE-2024-3400 to its catalog of known exploited vulnerabilities following reports of multiple groups attacking the flaw.

Palo Alto Networks itself has said it is aware of a growing number of attacks leveraging CVE-2024-3400 and has warned about proof-of-concept code for the flaw being publicly available.

According to Siemens, its Ruggedcom APE1808 product — commonly deployed as edge devices in industrial control environments — is vulnerable to the issue. Siemens described all versions of the product with PAN Virtual NGFW configured with the GlobalProtect gateway or GlobalProtect portal — or both — as affected by the vulnerability.

In an advisory, Siemens said it is working on updates for the bug and recommended specific countermeasures that customers should take in the meantime to mitigate risk. The measures include using specific threat IDs that PAN has released to block attacks targeting the vulnerability. Siemens' advisory pointed to PAN's recommendation to disable GlobalProtect gateway and GlobalProtect portal, and reminded customers that the features are already disabled by default in Ruggedcom APE1808 deployment environments.

PAN initially also recommended organizations disable device telemetry to protect against attacks targeting the flaw. The security vendor later withdrew that advice, citing ineffectiveness. "Device telemetry does not need to be enabled for PAN-OS firewalls to be exposed to attacks related to this vulnerability," the company noted.

Siemens urged customers, as a general rule, to protect network access to devices in industrial control environments with appropriate mechanisms, saying, "In order to operate the devices in a protected IT environment, Siemens recommends to configure the environment according to Siemens' operational guidelines for Industrial Security."

The Shadowserver Foundation, which monitors the Internet for threat related traffic, identified some 5,850 vulnerable instances of PAN's NGFW exposed and accessible over the Internet as of April 22. Some 2,360 of the vulnerable instances appear to be located in North America; Asia accounted for the next highest number with around 1,800 exposed instances.

**Internet-Exposed Devices Remain a Critical Risk for ICS/OT**

It's unclear how many of those exposed instances are in industrial control system (ICS) and operational technology (OT) settings. But generally, Internet exposure continues to be a major issue in ICS and OT environments. A new investigation by Forescout uncovered nearly 110,000 Internet-facing ICS and OT systems worldwide. The US led the way, accounting for 27% of the exposed instances. However, that number was significantly lower compared with a few years ago. In contrast, Forescout found a sharp increase in the number of Internet-exposed ICS/OT equipment in other countries, including Spain, Italy, France, Germany, and Russia.

"Opportunistic attackers are increasingly abusing this exposure at scale — sometimes with a very lax targeting rationale driven by trends, such as current events, copycat behavior, or the emergencies found in new, off-the-shelf capabilities or hacking guides," Forescout said. The security vendor assessed that the exposure had to do at least in part with systems integrators delivering packaged bundles with components in them that inadvertently expose ICS and OT systems to the Internet. "In all likeliness," Forescout said, "most asset owners are unaware these packaged units contain exposed OT devices."

**About the Author(s)**

Jai Vijayan is a seasoned technology reporter with over 20 years of experience in IT trade journalism. He was most recently a Senior Editor at Computerworld, where he covered information security and data privacy issues for the publication. Over the course of his 20-year career at Computerworld, Jai also covered a variety of other technology topics, including big data, Hadoop, Internet of Things, e-voting, and data analytics. Prior to Computerworld, Jai covered technology issues for The Economic Times in Bangalore, India. Jai has a Master's degree in Statistics and lives in Naperville, Ill.

Siemens Working on Fix for Device Affected by Palo Alto Firewall Bug

The infamous Russian threat actor has created a custom tool called GooseEgg to exploit CVE-2022-38028 in cyber-espionage attacks against targets in Ukraine, Western Europe, and North America.

Source: Science Photo Library via Alamy Stock Photo

A well-known Russian advanced persistent threat (APT) group has been using a custom tool to exploit a bug that been around for several years in the Windows Print Spooler service to elevate privileges and steal credentials in numerous intelligence-gathering attacks around the globe. It also appears to be paving the way for further attacks.

Fancy Bear (aka APT28, Forest Blizzard, Pawn Storm, Sofacy Group, and Strontium) is linked to the Russian General Staff Main Intelligence Directorate. It has been using a tool called GooseEgg since at least June 2020 and possibly as early as April 2019 to exploit the CVE-2022-38028 vulnerability in Windows Print Spooler service, Microsoft Threat Intelligence revealed in a blog post on April 22.

Microsoft patched the flaw, which allows an attacker who successfully exploits it to gain SYSTEM privileges, in October 2022. Fancy Bear is using GooseEgg to modify a JavaScript constraints file and execute it with SYSTEM-level permissions.

"While a simple launcher application, GooseEgg is capable of spawning other applications specified at the command line with elevated permissions, allowing threat actors to support any follow-on objectives such as remote code execution, installing a backdoor, and moving laterally through compromised networks," according to the post.

Microsoft discovered Fancy Bear deploying GooseEgg in attacks against various Ukrainian, Western European, and North American government, nongovernmental, education, and transportation sector organizations.

Windows Print Spooler, a printer services technology, is a popular target for attackers, who tend to pounce on numerous flaws affecting the software that manages the printing process in Windows. The most well-known of these is two security vulnerabilities collectively called PrintNightmare that were discovered in late June 2021 and spawned a series of well-documented attacks.

**GooseEgg Malware Tailored for Windows Print Spooler**

That Fancy Bear targeted the service itself is not out of the ordinary, according to Microsoft; however, its use of the newly discovered GooseEgg to elevate privileges in these attacks is a novel threat activity for the group. GooseEgg is typically deployed with a batch script that invokes a corresponding GooseEgg executable and sets up persistence as a scheduled task.

The GooseEgg binary then takes one of four commands, each with different runpaths. "While the binary appears to launch a trivial given command, in fact the binary does this in a unique and sophisticated manner, likely to help conceal the activity," according to the post.

Two of the binary's commands trigger the exploit for the Print Spooler flaw and launch either a provided dynamic link library (DLL) or executable with elevated permissions, while another command tests the exploit and checks that it has succeeded.

The name of an embedded malicious DLL file launched by GooseEgg typically includes the phrase "wayzgoose," such as wayzgoose23.dll. That DLL as well as other components of the malware are deployed to one of several installation subdirectories created under the Windows directory C:\\ProgramData, according to Microsoft Threat Intelligence.

The exploit ultimately replaces the C: drive symbolic link in the object manager to point to the newly created directory, resulting in Print Spooler being redirected to the actor-controlled directory containing the copied driver packages when it attempts to load this registry: C:\\Windows\\System32\\DriverStore\\FileRepository\\pnms009.inf\_amd64\_a7412a554c9bc1fd\\MPDW-Constraints.js.

Eventually, the auxiliary DLL wayzgoose.dll file launches in the context of the PrintSpooler service with SYSTEM permissions as "a basic launcher application capable of spawning other applications" with the same permissions, according to the post.

**Keeping Fancy Bear Cyber Espionage at Bay**

Fancy Bear has a history of attacking known vulnerabilities, particularly in Microsoft products, to compromise targets for its nefarious activities — which primarily involve, but are not limited to, intelligence gathering. Last year, it mounted a flurry of cyber-espionage attacks against government agencies in NATO countries and organizations in the Middle East that exploited CVE-2023-23397, a zero-click vulnerability in Microsoft's Outlook email client.

While the group's most high-profile attack may be its ties to hacking aimed at running interference in the 2016 US presidential elections, the group has been most notably active of late in various attacks against Ukraine since Russia's war against the country began in February 2022.

The best way that organizations can protect themselves against attacks from the Russian APT is to apply patches for the vulnerable products that it targets. Microsoft recommended that users apply the CVE-2022-38028 security update to mitigate the GooseEgg threat against Windows Print Spooler; meanwhile, the Microsoft Defender Antivirus detects the specific Forest Blizzard capability as HackTool:Win64/GooseEgg.

Another way to mitigate the issue is to disable the Windows Print Spooler service domain controller operations, since it isn't required, according to Microsoft. To help identify domain controllers that have the Print Spooler service enabled, Microsoft Defender for Identity has a built-in security assessment that tracks the availability of Print Spooler services on domain controllers.

Greg Fitzgerald, co-founder at Sevco Security, notes that printer bugs are particularly difficult to remediate because printers are often under-inventoried.

“Security teams have become incredibly efficient at identifying and remediating CVEs, but increasingly it's these environmental vulnerabilities that create security gaps giving malicious actors access to data," Fitzgerald says. "These vulnerabilities are hiding in plain sight throughout IT environments, creating a landscape of threats that security teams can’t see, but are still accountable for. The unfortunate reality is that most organizations are unable to create an accurate IT asset inventory that reflects the entirety of their attack surface. This puts them at the mercy of attackers who know where to look for forgotten IT assets that contain exploitable vulnerabilities.”

**About the Author(s)**

Elizabeth Montalbano is a freelance writer, journalist, and therapeutic writing mentor with more than 25 years of professional experience. Her areas of expertise include technology, business, and culture. Elizabeth previously lived and worked as a full-time journalist in Phoenix, San Francisco, and New York City; she currently resides in a village on the southwest coast of Portugal. In her free time, she enjoys surfing, hiking with her dogs, traveling, playing music, yoga, and cooking.

Russia's Fancy Bear Pummels Windows Print Spooler Bug

State-sponsored groups are targeting critical vulnerabilities in virtual private network (VPN) gateways, firewall appliances, and other edge devices to make life difficult for incident responders, who rarely have visibility into the devices.

Source: Wright Studio via Shutterstock

Earlier this year, Mandiant Consulting's incident response team tracked an attack by a China-linked espionage group back to the compromise of an edge device in its client's network, but because the appliance is a closed system, the victim of the attack had to request a forensic image from the maker of the network appliance.

Two months later, the client is still waiting.

This difficulty in detecting — and then investigating — compromises of edge appliances highlights why many nation-state attackers are increasingly targeting firewalls, email gateways, VPNs, and other devices, says Charles Carmakal, CTO for Mandiant Consulting at Google Cloud. The threat groups not only evade detection longer, but even when defenders get wind of the attack, investigating the incident is much more difficult.

It's a problem that Mandiant deals with "all the time," he says.

"We have much better telemetry for Windows computers today, mostly because of the maturity of EDR \[endpoint detection and response\] solutions," Carmakal says. "The telemetry on edge devices ... is often completely nonexistent. To be able to triage and forensically examine the device, you've got to get a forensic image, but you can't just open up the device and pull the hard drive out."

Espionage attackers' shift to exploiting edge devices is one of the major trends that Google Cloud's Mandiant Consulting saw in 2023, according to the M-Trends 2024 report published on April 23. Overall, the company tracked and reported on more than two dozen campaigns and global events in 2023 related to its investigations.

The amount of time an attacker is active on a compromised systems before detection, known as dwell time, continued to shrink — to 10 days in 2023, down from 16 days the previous year. Ransomware accounted for 23% of Mandiant's investigations in 2023, up from 18% in 2022. Companies became aware of most incidents (54%) because a third party — often the attacker themselves, in the case of ransomware — notified the victim.

With ransomware often notifying victims, external detection rose to 54%. Source: Google Cloud's Mandiant

**Attackers Move to Less Visible Environments**

While edge devices require knowledgeable attackers to compromise and control them, these high-availability environments also usually offer their own utilities and features to deal with native formats and functionality. By "living off the land" and using the built-in capabilities, attackers can build more reliable malware and still run less risk of being detected, because of the lack of visibility defenders have into the internal operations of the devices.

"\[M\]any of these devices are put through rigorous testing regimes by the manufacturer during development to ensure their stability," Mandiant stated in the report. "China-nexus malware developers take advantage of the built-in functionality included in these systems ... leveraging native capabilities \[that can\] reduce the overall complexity of the malware by instead weaponizing existing features within that have been rigorously tested by the organization."

In one incident, Mandiant consultants discovered the BoldMove backdoor malware, Chinese attackers crafted to infect a Fortinet device, disabling two logging features and allowing the attacker to remain undetected for a longer period. BoldMove was created specifically for Fortinet environments.

Incident response efforts are also often hampered by the lack of easy access for consultants and defenders to the underlying operating system. With no way to analyze the underlying code to seek out compromised devices, incident responders often cannot determine the root cause of a compromise, says Mandiant's Carmakal.

"Some vendors refuse to give forensic images, \[which\] I understand ... because they have a lot of intellectual property on the device," he says. "Companies need to understand the scope and extent of a compromise, and if it starts on a network device, and you need to look into that."

**Exploit Use Rises, More Data Leak Sites**

Attackers have doubled down on using exploits as the initial access point for attacks, with 38% of attacks Mandiant investigated where it could determine an initial vector starting with an exploit. Phishing, a distant second place, accounted for 17% of the initial actions in an attack. Running a close third, prior compromises inadvertently left exploitable accounted for 15% of all initial access vectors.

"Attackers continue to leverage effective tactics to gain access to target environments and conduct their operations," the Mandiant report stated. "While the most popular infection vectors fluctuate, organizations must focus on defense-in-depth strategies. This approach can help mitigate the impact of both common and less frequent initial intrusion methods."

Finally, Mandiant investigators have also seen data leak sites (DLS) increase over time, which now account for more than a third (36%) of all financially motivated attacks.

**About the Author(s)**

Veteran technology journalist of more than 20 years. Former research engineer. Written for more than two dozen publications, including CNET News.com, Dark Reading, MIT's Technology Review, Popular Science, and Wired News. Five awards for journalism, including Best Deadline Journalism (Online) in 2003 for coverage of the Blaster worm. Crunches numbers on various trends using Python and R. Recent reports include analyses of the shortage in cybersecurity workers and annual vulnerability trends.

Teetering on the Edge: VPNs, Firewalls' Nonexistent Telemetry Lures APTs

The irony is lost on few, as a nation-state threat actor used eight MITRE techniques to breach MITRE itself — including exploiting the Ivanti bugs that attackers have been swarming on for months.

Source: Kristoffer Tripplaar via Alamy Stock Photo

Foreign nation-state hackers have used vulnerable Ivanti edge devices to gain three months' worth of "deep" access to one of MITRE Corp.'s unclassified networks.

MITRE, steward of the ubiquitous ATT&CK glossary of commonly known cyberattack techniques, previously went 15 years without a major incident. The streak snapped in January when, like so many other organizations, its Ivanti gateway devices were exploited.

The breach affected the Networked Experimentation, Research, and Virtualization Environment (NERVE), an unclassified, collaborative network the organization uses for research, development, and prototyping. The extent of the NERVE damage (pun intended) is currently being assessed.

Dark Reading reached out to MITRE to confirm the timeline and details of the attack. MITRE did not provide further clarification.

**MITRE's ATT&CK**

Stop me if you've heard this one before: In January, after an initial reconnaissance period, a threat actor exploited one of the company's virtual private networks (VPNs) through two Ivanti Connect Secure zero-day vulnerabilities (ATT&CK technique T1190, Exploit Public-Facing Applications).

According to a blog post from MITRE's Center for Threat-Informed Defense, the attackers bypassed the multifactor authentication (MFA) protecting the system with some session hijacking (MITRE ATT&CK T1563, Remote Service Session Hijacking).

They attempted to leverage several different remote services (T1021, Remote Services), including the Remote Desktop Protocol (RDP) and Secure Shell (SSH), to gain access to a valid administrator account (T1078, Valid Accounts). With it, they pivoted and "dug deep" into the network's VMware virtualization infrastructure.

There, they deployed Web shells (T1505.003, Server Software Component: Web Shell) for persistence, and backdoors to run commands (T1059, Command and Scripting Interpreter) and steal credentials, exfiltrating any stolen data to a command-and-control server (T1041, Exfiltration Over C2 Channel). To hide this activity, the group created its own virtual instances to run within the environment (T1564.006, Hide Artifacts: Run Virtual Instance).

**MITRE's Defense**

"The impact of this cyberattack should not be taken lightly," says Darren Guccione, CEO and co-founder at Keeper Security, highlighting "both the foreign ties of the attackers and the ability of the attackers to exploit two serious zero-day vulnerabilities in their quest to compromise MITRE’s NERVE, which could potentially expose sensitive research data and intellectual property."

He posits, "Nation-state actors often have strategic motivations behind their cyber operations, and the targeting of a prominent research institution like MITRE, that works on behalf of the US government, could be just one component of a larger effort."

Whatever its goals were, the hackers had ample time to carry them out. Though the compromise occurred in January, MITRE was only able to detect it in April, leaving a quarter-year gap in between.

"MITRE followed best practices, vendor instructions, and the government’s advice to upgrade, replace, and harden our Ivanti system," the organization wrote on Medium, "but we did not detect the lateral movement into our VMware infrastructure. At the time we believed we took all the necessary actions to mitigate the vulnerability, but these actions were clearly insufficient."

Editor's note: An earlier version of the story attributed the attacks to UNC5221. That attribution has not been made at this time.

**About the Author(s)**

Nate Nelson is a freelance writer based in New York City. Formerly a reporter at Threatpost, he contributes to a number of cybersecurity blogs and podcasts. He writes "Malicious Life" -- an award-winning Top 20 tech podcast on Apple and Spotify -- and hosts every other episode, featuring interviews with leading voices in security. He also co-hosts "The Industrial Security Podcast," the most popular show in its field.

MITRE ATT&amp;CKED: InfoSec's Most Trusted Name Falls to Ivanti Bugs

By Deeba Ahmed
IT professionals are under attack! This article exposes a malicious malvertising campaign targeting IT teams with a novel backdoor named MadMxShell. Learn how attackers use typosquatting and DNS techniques to compromise systems.
This is a post from HackRead.com Read the original post: Malvertising: Fake Popular Software Ads Deliver New MadMxShell Backdoor

In a recent wave of cyberattacks, IT professionals have become the target of a cunning malvertising campaign uncovered by Zscaler ThreatLabz researchers Roy Tay and Sudeep Singh.

According to the company’s research, this campaign leverages deceptive online advertisements to distribute a previously unseen backdoor named “MadMxShell.” It all started in March 2024, when Zscaler ThreatLabz discovered a threat actor using look-alike domains to distribute MadMxShell, utilizing DLL sideloading, DNS protocol abuse, and memory forensics security solutions.

Researchers believe the attackers have displayed a calculated approach. Between November 2023 and March 2024, attackers registered multiple domain names closely resembling those of popular IP scanner and network administration software, including Advanced IP Scanner, Angry IP Scanner, PRTG IP Scanner by Paessler, Manage Engine, and network admin tasks related to VLANs.

This tactic is known as typosquatting. It creates a high chance that the domains will appear on top searches and IT professionals might click on the malicious advertisement by mistake. 

Once clicked, the ad redirects the user to a landing page designed to look like the genuine software vendor’s website. Here, they’re presented with a downloadable file that, unbeknownst to them, harbours the MadMxShell backdoor.

****New Backdoor with Evasive Techniques****

As per Zscaler’s blog post, the MadMxShell backdoor employs a multi-stage deployment process designed to evade detection by traditional security solutions. The initial payload leverages DLL sideloading, a technique where a legitimate program is tricked into loading a malicious library file. This malicious library then downloads additional components that establish communication with the attacker’s command-and-control (C2) server.

One of the most concerning aspects of MadMxShell is its use of DNS MX record queries for C2 communication. This technique leverages the standard Domain Name System (DNS) protocol in an unconventional way to mask communication with the attacker’s infrastructure. Additionally, MadMxShell employs anti-dumping techniques to prevent memory analysis, making it difficult for security researchers to understand its inner workings.

****Protecting Your Systems:****

To mitigate risks, be cautious of unsolicited ads, enable pop-up blockers, maintain robust security software, and educate employees about the dangers of malvertising and social engineering tactics.

Jason Soroko, Senior Vice President of Products at Sectigo commented on the new campaign. _“_Defenders don’t usually look for malicious control communications (C2) in email exchange DNS traffic, so the attackers in this case found a place to hide. The attackers also employ a technique that blocks the ‘dumping’ of memory for analysis by endpoint security solutions,” Jason explained.

_“_Malvertising isn’t new, however, the malware techniques being used here demonstrate that the technology pipeline of the attackers is deep and a great deal of thought has been put into hiding in the dark corners of networking and operating systems,_“_ he wanted.

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