TALOS

The exploit researcher recently rejoined Talos after starting her career with the company’s predecessor  By Jonathan Munshaw.  Lurene Grenier says state-sponsored threat actors keep her up at night, even after years of studying and following them.   She’s spent her security career warning people why this was going to be a problem.  Today if someone is compromised by a well-funded, state-sponsored actor, she is concerned but doesn’t necessarily feel sorry. After all, she’s been warning the security community about this for years.  “You think about the phrase ‘fool me once, shame on you...’ Five years ago if we had this discussion and you were hit with an attack, you’d think ‘shame on China,’” she said. “Today, if we have that discussion about why you were hit, it’s shame on us.”  Grenier has spent her career looking at state-sponsored actor trends and writing detection content to block those actors. She was one of the first of the smaller research staff at the Sourcefire Vulnerability...

Talos is publishing a glimpse into the most prevalent threats we've observed from July 22 - 29. As with previous roundups, this post isn't meant to be an in-depth analysis. Instead, this post will summarize the threats we've observed by highlighting key behavioral characteristics, indicators of compromise and discussing how our customers are automatically protected from these threats. As a reminder, the information provided for the following threats in this post is non-exhaustive and current as of the date of publication. Additionally, please keep in mind that IOC searching is only one part of threat hunting. Spotting a single IOC does not necessarily indicate maliciousness. Detection and coverage for the following threats is subject to updates, pending additional threat or vulnerability analysis. For the most current information, please refer to your Firepower Management Center, Snort.org, or ClamAV.net. For each threat described below, this blog post only lists 25 of the associate...

By Jon Munshaw.  Welcome to this week’s edition of the Threat Source newsletter.  Between the White House’s recent meeting, countless conference talks and report after report warning of cybersecurity burnout, there’s been a ton of talk recently around the cybersecurity skills gap and hiring.  Everyone wants to know the magic ticket to figure out how to increase hiring at their cybersecurity practice without hiring somehow with under-developed skills that could leave clients open to attack. This is not a problem exclusive to cybersecurity, but I do find it interesting that there’s been so much talk about the problems the cybersecurity workforce faces and not much about actual solutions.  I think a good place to start would change the meaning of what an “entry-level” position truly is in security. I came into this field with zero security experience from the domain of journalism. My family considered me to be “a computer guy” just because I was good at searching the internet fo...

By Francesco Benvenuto.  Recently, I was performing some research on a wireless router and noticed the following piece of code:  This unescape function will revert the URL encoded bytes to its original form. But something specifically caught my attention: There was no size check for the performed operations and the function assumes that after a ‘%’ there are always two bytes. So, what would happen if after ‘%’, only one character existed? The answer is that the s+3, in the strcpy, will access after the end of the string. So, it could lead to memory corruption. Then, I tried to exploit this bug on the router in question. But based on how the URL string was managed in that device, it was not possible. But it had the potential to crash other web servers that used this piece of code. That function belonged to the freshtomato library. So, I searched for the source code and noticed that at the beginning of the file containing that function, there was the following comment:  It was code fr...

By Nate Pors and Terryn Valikodath.   Executive summary  In a recent malspam campaign delivering the Qakbot banking trojan, Cisco Talos Incident Response (CTIR) observed the adversary using aggregated, old email threads from multiple organizations that we assess were likely harvested during the 2021 ProxyLogon-related compromises targeting vulnerable Microsoft Exchange servers.  This campaign relies on external thread hijacking, whereby the adversary is likely using a bulk aggregation of multiple organizations’ harvested emails to launch focused phishing campaigns against previously uncompromised organizations. This differs from the more common approach to thread hijacking, in which attackers use a single compromised organization’s emails to deliver their threat.  This many-to-one approach is unique from what we have generally observed in the past and is likely an indirect effect of the widespread compromises and exfiltration of large volumes of email from 2020 and 2021.  Understandi...

Commodity malware usage surpasses ransomware by narrow margin  By Caitlin Huey. For the first time in more than a year, ransomware was not the top threat Cisco Talos Incident Response (CTIR) responded to this quarter, as commodity malware surpassed ransomware by a narrow margin. This is likely due to several factors, including the closure of several ransomware groups, whether it be of their own volition or the actions of global law enforcement agencies and governments.  Commodity malware was the top observed threat this quarter, a notable development given the general decrease in observations of attacks leveraging commodity trojans in CTIR engagements since 2020. These developments coincide with a general resurgence of certain email-based trojans in recent months, as law enforcement and technology companies have continued to attempt to disrupt and affect email-based malware threats like Emotet and Trickbot. This quarter featured malware such as the Remcos remote access trojan ...

Today, Talos is publishing a glimpse into the most prevalent threats we've observed between July 15 and July 22. As with previous roundups, this post isn't meant to be an in-depth analysis. Instead, this post will summarize the threats we've observed by highlighting key behavioral characteristics, indicators of compromise, and discussing how our customers are automatically protected from these threats. As a reminder, the information provided for the following threats in this post is non-exhaustive and current as of the date of publication. Additionally, please keep in mind that IOC searching is only one part of threat hunting. Spotting a single IOC does not necessarily indicate maliciousness. Detection and coverage for the following threats is subject to updates, pending additional threat or vulnerability analysis. For the most current information, please refer to your Firepower Management Center, Snort.org, or ClamAV.net. For each threat described below, this blog post only lists 2...

By Jon Munshaw.  Welcome to this week’s edition of the Threat Source newsletter.  I could spend time in this newsletter every week talking about fake news. There are always so many ridiculous memes, headlines, misleading stories, viral Facebook posts and manipulated media that I see come across my Instagram feed or via my wife when she shows me TikToks she favorited.  One recent event, though, was so crushing to me that I had to call it out specifically. Former Japanese Prime Minister Shinzo Abe was assassinated earlier this month while making a campaign speech in public. This was a horrible tragedy marking the death of a powerful politician in one of the world’s most influential countries. It was the top story in the world for several days and was even more shocking given Japan’s strict gun laws and the relative infrequency of any global leaders being the target of violence.  It took no time for the internet at large to take this tragedy and immediately try to spin it to the...

Executive summary Since the Russian invasion of Ukraine began, Ukrainians have been under a nearly constant barrage of cyber attacks. Working jointly with Ukrainian organizations, Cisco Talos has discovered a fairly uncommon piece of malware targeting Ukraine — this time aimed at a large software development company whose software is used in various state organizations within Ukraine. We believe that this campaign is likely sourced by Russian state-sponsored actors or those acting in their interests. As this firm is involved in software development, we cannot ignore the possibility that the perpetrating threat actor's intent was to gain access to source a supply chain-style attack, though at this time we do not have any evidence that they were successful. Cisco Talos confirmed that the malware is a slightly modified version of the open-source backdoor named "GoMet." The malware was first observed on March 28, 2022. GoMet backdoor The story of this backdoor is rather curious — ther...

Emmanuel Tacheau of Cisco Talos discovered these vulnerabilities. Blog by Jon Munshaw.  Cisco Talos recently discovered a use-after-free vulnerability in Accusoft ImageGear's PSD header processing function.  The ImageGear library is a document-imaging developer toolkit that allows users to create, edit, annotate and convert various images. It supports more than 100 file formats such as DICOM, PDF and Microsoft Office.  This vulnerability, TALOS-2022-1526 (CVE-2022-29465) could allow an attacker to cause a use-after-free condition by tricking the targeted user into opening a malformed .psd file in the application. The vulnerability leads to out-of-bounds heap writes, which causes memory corruption and, possibly, code execution. In adherence to Cisco’s vulnerability disclosure policy, Accusoft patched this issue and released an update for ImageGear. Talos tested and confirmed Accusoft ImageGear, version 19.10, is affected by this vulnerability.  The following Snort rules will detect ...