Money Laundering 101, and why Joe is worried

Welcome to this week's edition of the Threat Source newsletter. Howdy friends! One of things I learned early on in cyber security is that crime does, in fact, pay. It can pay very well, actually. If it didn't, we wouldn't have ransomware cartels raking in obscene amounts of money year after year...

Tomorrow, and tomorrow, and tomorrow: Information security and the Baseball Hall of Fame

Welcome to this week's edition of the Threat Source newsletter. "Tomorrow, and tomorrow, and tomorrow / Creeps in this petty pace from day to day / To the last syllable of recorded time." - Shakespeare's Macbeth "But I am very poorly today and very stupid and I hate everybody and everything. One...

UAT-5918 targets critical infrastructure entities in Taiwan

By Jung soo An, Asheer Malhotra, Brandon White, and Vitor Ventura. Cisco Talos discovered a malicious campaign we track under the UAT-5918 umbrella that has been active since at least 2023. UAT-5918, a threat actor believed to be motivated by establishing long-term access for information theft,...

Miniaudio and Adobe Acrobat Reader vulnerabilities

Cisco Talos' Vulnerability Discovery & Research team recently disclosed a Miniaudio and three Adobe vulnerabilities. The vulnerabilities mentioned in this blog post have been patched by their respective vendors, all in adherence to Cisco 's third-party vulnerability disclosure policy. For Snort...

Patch it up: Old vulnerabilities are everyone’s problems

Welcome to this week's edition of the Threat Source newsletter. Let's pick up where we left off in my last newsletter. Please mark your calendars: The free support for Windows 10 will end on October 14, 2025. When a software loses vendor support, it no longer receives patches or updates. As...

Abusing with style: Leveraging cascading style sheets for evasion and tracking

Cisco Talos has identified actors abusing Cascading Style Sheets CSS to 1 evade spam filters and detection engines, and 2 track users' actions and preferences. This blog is a follow-up to our previous report on how threat actors could abuse CSS using a technique called "hidden text salting" to...

Microsoft Patch Tuesday for March 2025 — Snort rules and prominent vulnerabilities

Microsoft has released its monthly security update for March of 2025 which includes 57 vulnerabilities affecting a range of products, including 6 that Microsoft marked as "critical". There are six vulnerabilities that Microsoft has observed being exploited in the wild. CVE-2025-26633 is a Remoted...

Who is Responsible and Does it Matter?

Welcome to this week's edition of the Threat Source newsletter. At Talos we bat on behalf of our customers, protecting them against all manner of cyber threats that may affect them. The nature of the threat actor and their origin or affiliation makes no difference; if they are attacking or planni...

Unmasking the new persistent attacks on Japan

Cisco Talos discovered malicious activities conducted by an unknown attacker since as early as January 2025, predominantly targeting organizations in Japan. The attacker has exploited the vulnerability CVE-2024-4577, a remote code execution RCE flaw in the PHP-CGI implementation of PHP on Windows...

Sellers can get scammed too, and Joe goes off on a rant about imposter syndrome

Welcome to this week's edition of the Threat Source newsletter. Hello again my friends! Geez, it's been a year am I right? Lemons its February you say?! Oof. Imposter syndrome. You've heard the term I'm sure, but what is it? Basically: imposter syndrome is the persistent feeling of self-doubt and...

Lotus Blossom espionage group targets multiple industries with different versions of Sagerunex and hacking tools

Cisco Talos discovered multiple cyber espionage campaigns that target government, manufacturing, telecommunications and media, delivering Sagerunex and other hacking tools for post-compromise activities. Talos attributes these attacks to the threat actor known as Lotus Blossom. Lotus Blossom has...

Your item has sold! Avoiding scams targeting online sellers

There are many risks associated with selling items on online marketplaces that individuals and organizations should be aware of when conducting business on these platforms. Many of the general recommendations related to the use of these platforms are tailored towards purchasing items; however,...

Efficiency? Security? When the quest for one grants neither.

Welcome to this week's edition of the Threat Source newsletter. Benjamin Franklin once said, "Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety." In much the same way, those who rush for efficiency without taking into account...

Weathering the storm: In the midst of a Typhoon

Summary Cisco Talos has been closely monitoring reports of widespread intrusion activity against several major U.S. telecommunications companies. The activity, initially reported in late 2024 and later confirmed by the U.S. government, is being carried out by a highly sophisticated threat actor...

ClearML and Nvidia vulns

Cisco Talos' Vulnerability Discovery & Research team recently disclosed two vulnerabilities in ClearML and four vulnerabilities in Nvidia. The vulnerabilities mentioned in this blog post have been patched by their respective vendors, all in adherence to Cisco 's third-party vulnerability disclosu...

Changing the narrative on pig butchering scams

Welcome to this week's edition of the Threat Source Newsletter. Love is in the air this week. Wait, is that love? Or is it some tech bro with a housing development company that would totally love to meet in person but can't this week emailing you about an investment opportunity in his...

Microsoft Patch Tuesday for February 2025 — Snort rules and prominent vulnerabilities

Microsoft has released its monthly security update for February of 2025 which includes 63 vulnerabilities affecting a range of products, including 4 that Microsoft marked as "critical" and one marked as "moderate." There are two notable "critical" vulnerabilities. The first is CVE-2025-21376, whi...

Small praise for modern compilers - A case of Ubuntu printing vulnerability that wasn’t

By Aleksandar Nikolich Earlier this year, we conducted code audits of the macOS printing subsystem, which is heavily based on the open-source CUPS package. During this investigation, IPP-USB protocol caught our attention. IPP over USB specification defines how printers that are available over USB...

Changing the tide: Reflections on threat data from 2024

"Enough Ripples, And You Change The Tide. For The Future Is Never Truly Set." X-Men: Days of Future Past In January, I dedicated some time to examine threat data from 2024, comparing it with the previous years to identify anomalies, spikes, and changes. As anticipated, the number of Common...

Google Cloud Platform Data Destruction via Cloud Build

Background & Public Research Google Cloud Platform GCP Cloud Build is a Continuous Integration/Continuous Deployment CI/CD service offered by Google that is utilized to automate the building, testing and deployment of applications. Orca Security published an article describing certain aspects of...

Defeating Future Threats Starts Today

Welcome to this week's edition of the Threat Source newsletter. You don't need me to tell you that security is constantly changing and that more change is on its way. The enthusiastic adoption of new AI systems will inevitably lead to more demands on cybersecurity teams. Not only will these syste...

Talos IR trends Q4 2024: Web shell usage and exploitation of public-facing applications spike

Threat actors increasingly deployed web shells against vulnerable web applications and primarily exploited vulnerable or unpatched public-facing applications to gain initial access in Q4, a notable shift from previous quarters. The functionality of the web shells and targeted web applications...

Whatsup Gold, Observium and Offis vulnerabilities

Cisco Talos' Vulnerability Research team recently disclosed three vulnerabilities in Observium, three vulnerabilities in Offis, and four vulnerabilities in Whatsup Gold. These vulnerabilities exist in Observium, a network observation and monitoring system; Offis DCMTK, a collection of libraries a...

New TorNet backdoor seen in widespread campaign

Cisco Talos discovered an ongoing malicious campaign operated by a financially motivated threat actor since as early as July 2024 targeting users, predominantly in Poland and Germany, based on the phishing email language. The actor has delivered different payloads, including Agent Tesla, Snake...

Seasoning email threats with hidden text salting

Cisco Talos observed an increase in the number of email threats leveraging hidden text salting also known as "poisoning" in the second half of 2024. Hidden text salting is a simple yet effective technique for bypassing email parsers, confusing spam filters, and evading detection engines that rely...

Everything is connected to security

Welcome to this week's edition of the Threat Source newsletter. Hello friends! Joe here again! I have just returned from the frozen northern tundra of Fargo, North Dakota. This was my first real visit to the frigid climates of the Midwest, and I have to say, they take cold to a new level. I was...

Find the helpers

Welcome to this week's edition of the Threat Source newsletter. "When I was a boy and I would see scary things in the news, my mother would say to me, 'Look for the helpers. You will always find people who are helping.'" ― Fred Rogers There's no world where following Mr. Roger's advice is wrong...

Slew of WavLink vulnerabilities

Lilith of Cisco Talos discovered these vulnerabilities. Forty-four vulnerabilities and sixty-three CVEs were discovered across ten .cgi and three .sh files, as well as the static login page, of the Wavlink AC3000 wireless router web application. The Wavlink AC3000 wireless router is one of the mo...

Microsoft Patch Tuesday for January 2025 — Snort rules and prominent vulnerabilities

Microsoft has released its monthly security update for January of 2025 which includes 159 vulnerabilities, including 12 that Microsoft marked as "critical." The remaining vulnerabilities listed are classified as "important." One notable critically rated vulnerability that has been patched this...

Do we still have to keep doing it like this?

Welcome to the first edition of the Threat Source newsletter for 2025. Upon returning to work this week from my Lindt chocolate reindeer coma, my first task was to write this newsletter. As I stared at a blank template hoping for inspiration to suddenly strike, I did what any security professiona...

Welcome to the party, pal!

Welcome to the final Threat Source newsletter of 2024. Watching "Die Hard" during the Christmas season has become a widely recognized tradition for many, despite ongoing debates about its classification as a Christmas movie. I know it isn't everyone's cup of tea. Whether you like the movie or not...

Acrobat out-of-bounds and Foxit use-after-free PDF reader vulnerabilities found

Cisco Talos' Vulnerability Research team recently disclosed three out-of-bounds read vulnerabilities in Adobe Acrobat Reader, and two use-after-free vulnerabilities in Foxit Reader. These vulnerabilities exist in Adobe Acrobat Reader and Foxit Reader, two of the most popular and feature-rich PDF...

Exploring vulnerable Windows drivers

This post is the result of research into the real-world application of the Bring Your Own Vulnerable Driver BYOVD technique along with Cisco Talos' series of posts about malicious Windows drivers. Some of this research was presented at the AVAR conference in Chennai at the beginning of December...

Something to Read When You Are On Call and Everyone Else is at the Office Party

Welcome to this week's edition of the Threat Source newsletter. The new head of the UK's National Cyber Security Centre, Richard Horne, recently remarked that there is a "clearly widening gap between, on the one hand, the threat and our exposure to it and, on the other, the defences that are in...

The evolution and abuse of proxy networks

As long as we've had the internet, users have tried to obfuscate how and what they are connecting to. In some cases, this is to work around restrictions put in place by governments or a desire to access content that is not otherwise available in a given region. This is why technologies like VPNs...

Microsoft Patch Tuesday for December 2024 contains four critical vulnerabilities

The Patch Tuesday for December of 2024 includes 72 vulnerabilities, including four that Microsoft marked as "critical." The remaining vulnerabilities listed are classified as "important." Microsoft assessed that exploitation of the four "critical" vulnerabilities is "less likely." CVE-2024-49112 ...

MC LR Router and GoCast unpatched vulnerabilities

Cisco Talos' Vulnerability Research team recently discovered two vulnerabilities in MC Technologies LR Router and three vulnerabilities in the GoCast service. These vulnerabilities have not been patched at time of this posting. For Snort coverage that can detect the exploitation of these...

The adventures of an extroverted cyber nerd and the people Talos helps to fight the good fight

Welcome to this week's edition of the Threat Source newsletter. I am unbelievably lucky to do the work that I do. My title is technically 'Senior Security Strategist'. It's a very fancy title, but basically: I get to research threats with my colleagues and friends to keep people safe here at Talo...

Finding vulnerabilities in ClipSp, the driver at the core of Windows’ Client License Platform

By Philippe Laulheret ClipSP clipsp.sys is a Windows driver used to implement client licensing and system policies on Windows 10 and 11 systems. Cisco Talos researchers have discovered eight vulnerabilities related to clipsp.sys ranging from signature bypass to elevation of privileges and sandbox...

Bidirectional communication via polyrhythms and shuffles: Without Jon the beat must go on

Welcome to this week's edition of the Threat Source newsletter. Bidirectional communication is foundational to a well-built team regardless of environment. It's critical in information security to be able to drive a conversation up the ladder and down and not lose the critical elements. One of th...

Malicious QR Codes: How big of a problem is it, really?

QR codes are disproportionately effective at bypassing most anti-spam filters, as most filters are not designed to recognize that a QR code is present in an image and decode the QR code. According to Cisco Talos' data, roughly 60% of all email containing a QR code is spam. Talos discovered two...

New PXA Stealer targets government and education sectors for sensitive information

Cisco Talos discovered a new information stealing campaign operated by a Vietnamese-speaking threat actor targeting government and education entities in Europe and Asia. We discovered a new Python program called PXA Stealer that targets victims' sensitive information, including credentials for...

November Patch Tuesday release contains three critical remote code execution vulnerabilities

The Patch Tuesday for November of 2024 includes 89 vulnerabilities, including four that Microsoft marked as "critical." The remaining vulnerabilities listed are classified as "important." Microsoft assessed that exploitation of the four "critical" vulnerabilities is "less likely." CVE-2024-43639 ...

Unwrapping the emerging Interlock ransomware attack

Cisco Talos Incident Response Talos IR recently observed an attacker conducting big-game hunting and double extortion attacks using the relatively new Interlock ransomware. Our analysis uncovered that the attacker used multiple components in the delivery chain including a Remote Access Tool RAT...

NVIDIA shader out-of-bounds and eleven LevelOne router vulnerabilities

Cisco Talos' Vulnerability Research team recently discovered five Nvidia out-of-bounds access vulnerabilities in shader processing, as well as eleven LevelOne router vulnerabilities spanning a range of possible exploits. For Snort coverage that can detect the exploitation of these vulnerabilities...

Threat actors use copyright infringement phishing lure to deploy infostealers

Cisco Talos has observed an unknown threat actor conducting a phishing campaign targeting Facebook business and advertising account users in Taiwan. The decoy email and fake PDF filenames are designed to impersonate a company's legal department, attempting to lure the victim into downloading and...

Writing a BugSleep C2 server and detecting its traffic with Snort

In June 2024, security researchers published their analysis of a novel implant dubbed "MuddyRot"aka "BugSleep". This remote access tool RAT gives operators reverse shell and file input/output I/O capabilities on a victim's endpoint using a bespoke command and control C2 protocol. This blog will...

How LLMs could help defenders write better and faster detection

Most users will associate large language models LLMs like ChatGPT with answering basic questions or helping to write basics lines of text. But could these tools actually help defenders in the cybersecurity industry write more effective detection content? Several security researchers from across...

Talos IR trends Q3 2024: Identity-based operations loom large

Threat actors are increasingly conducting identity-based attacks across a range of operations that are proving highly effective, with credential theft being the main goal in a quarter of incident response engagements. These attacks were primarily facilitated by living-off-the-land binaries LoLBin...

Threat Spotlight: WarmCookie/BadSpace

WarmCookie is a malware family that emerged in April 2024 and has been distributed via regularly conducted malspam and malvertising campaigns. WarmCookie, observed being used for initial access and persistence, offers a means for continuous long-term access to compromised environments and is used...