Using AI to defeat AI

Welcome to this week's edition of the Threat Source newsletter. Generative AI and agentic AI are here to stay. Although I believe that the advantages that AI brings to bad guys may be overstated, these new technologies allow threat actors to conduct attacks at a faster rate than before. One...

“Good enough” emulation: Fuzzing a single thread to uncover vulnerabilities

A Cisco Talos researcher worked around the limitations of hardware-level Code Read-out Protection RDP on the Socomec DIRIS M-70 gateway by pivoting from physical debugging to a "good enough" emulation approach. By focusing on emulating only the single thread responsible for Modbus protocol handli...

Hand over the keys for Shannon’s shenanigans

Welcome to this week's edition of the Threat Source newsletter. Last week, yet another security AI tool made the rounds on social media: Shannon, a fully autonomous AI penetration testing tool created by Keygraph. It "autonomously hunts for attack vectors in your code, then uses its built-in...

Ryan Liles, master of technical diplomacy

Cisco Talos is back with another inside look at the people who keep the internet safe. This time, Amy chats with Ryan Liles, who bridges the gap between Cisco's product teams and the third-party testing labs that put Cisco products through their paces. Ryan pulls back the curtain on the delicate...

New threat actor, UAT-9921, leverages VoidLink framework in campaigns

Cisco Talos recently discovered a new threat actor, UAT-9921, leveraging VoidLink in campaigns. Their activities may go as far back as 2019, even without VoidLink. The VoidLink compile-on-demand feature lays down the foundations for AI-enabled attack frameworks, which can create tools on-demand f...

Microsoft Patch Tuesday for February 2026 — Snort rules and prominent vulnerabilities

Microsoft has released its monthly security update for February 2026, which includes 59 vulnerabilities affecting a range of products, including two that Microsoft marked as "Critical". CVE-2026-21522 is a critical elevation of privilege vulnerability affecting Microsoft ACI Confidential...

All gas, no brakes: Time to come to AI church

Welcome to this week's edition of the Threat Source newsletter. Brothers and sisters, gather close for a moment. We are all security followers here gathered in fellowship and community, with one joyful spirit to fight the good fight and do good out there in the security world. It is with that...

Knife Cutting the Edge: Disclosing a China-nexus gateway-monitoring AitM framework

Cisco Talos uncovered "DKnife," a fully featured gateway-monitoring and adversary-in-the-middle AitM framework comprising seven Linux-based implants that perform deep-packet inspection, manipulate traffic, and deliver malware via routers and edge devices. Based on the artifact metadata, DKnife ha...

I'm locked in!

Welcome to this week's edition of the Threat Source newsletter. I've struggled a lot over the last few years with balance. I want to follow the news closely, but at the same time, I want to block everything out for self-preservation. Add in the fact that I love history and I'm an empath, and you'...

Microsoft releases update to address zero-day vulnerability in Microsoft Office

Microsoft has published three out-of-band OOB updates so far in January 2026. One of these updates was released to address a vulnerability, CVE-2026-21509, affecting Microsoft Office that has been reportedly exploited in the wild. Additional OOB updates have been published to resolve operational...

Dissecting UAT-8099: New persistence mechanisms and regional focus

Cisco Talos has identified a new campaign by UAT-8099, active from late 2025 to early 2026, that is targeting vulnerable Internet Information Services IIS servers across Asia with a specific focus on victims in Thailand and Vietnam. Analysis confirms significant operational overlaps between this...

IR Trends Q4 2025: Exploitation remains dominant, phishing campaign targets Native American tribal organizations

Threat actors predominately exploited public-facing applications for the second quarter in a row, with this tactic appearing in nearly 40 percent of Cisco Talos Incident Response Talos IR engagements -- a notable decrease from over 60 percent last quarter, when engagements involving ToolShell...

I scan, you scan, we all scan for... knowledge?

Welcome to this week's edition of the Threat Source newsletter. " Upon us all a little rain must fall" -- Led Zeppelin, via Henry Wadsworth Longfellow I recently bumped into a colleague with whom I spent several years working in an MSSP environment. We had very different roles within the...

Foxit, Epic Games Store, MedDreams vulnerabilities

Cisco Talos' Vulnerability Discovery & Research team recently disclosed three vulnerabilities in Foxit PDF Editor, one in the Epic Games Store, and twenty-one in MedDream PACS. The vulnerabilities mentioned in this blog post have been patched by their respective vendors, all in adherence to Cisco...

Predicting 2026

Welcome to this week's edition of the Threat Source newsletter. It's become traditional at this time of year to make predictions about cybersecurity for the coming year. Obviously, no one has a crystal ball to predict the future, and if they did, they would be quietly making a fortune rather than...

UAT-8837 targets critical infrastructure sectors in North America

Cisco Talos is closely tracking UAT-8837, a threat actor we assess with medium confidence is a China-nexus advanced persistent threat APT actor based on overlaps in tactics, techniques, and procedures TTPs with those of other known China-nexus threat actors. Based on UAT-8837's TTPs and...

Brushstrokes and breaches with Terryn Valikodath

Cisco Talos is kicking off the new year with a behind-the-scenes look at incident response through the eyes of Terryn Valikodath, Senior Incident Response Consultant at Talos. In this episode, Amy sits down with Terryn to explore the realities of a job that blends technical know-how with...

Microsoft Patch Tuesday for January 2026 — Snort rules and prominent vulnerabilities

Microsoft has released its monthly security update for January 2026, which includes 112 vulnerabilities affecting a range of products, including 8 that Microsoft marked as "critical". In this month's release, Microsoft observed one of the included "important" vulnerabilities, CVE-2026-20805, as...

Resolutions, shmesolutions (and what’s actually worked for me)

Welcome to this week's edition of the Threat Source newsletter. I went to bed at 8:30 p.m. on New Year's Eve, and I think that's pretty indicative of how I approach the whole idea of New Year's resolutions. I love to count down to the new year with loved ones as much as the next person, but I hav...

UAT-7290 targets high value telecommunications infrastructure in South Asia

Cisco Talos is disclosing a sophisticated threat actor we track as UAT-7290, who has been active since at least 2022. UAT-7290 is tasked with gaining initial access as well as conducting espionage focused intrusions against critical infrastructure entities in South Asia. UAT-7290's arsenal includ...

How Cisco Talos powers the solutions protecting your organization

Cisco Talos is Cisco's threat intelligence and security research organization that powers Cisco's product portfolio with that intelligence. While we are well known for the security research in our blog, vulnerability discoveries, and our open-source software, you may not be aware of exactly how o...

Adios 2025, you won’t be missed

Welcome to this week's edition of the Threat Source newsletter. For us in America, we're in the holiday doldrums and things slow and/or shut down until the new year. At Cisco, we shut down the last week of the year to reset and recharge, and I've grown to be quite fond of it. I've worked plenty o...

Libbiosig, Grassroot DiCoM, Smallstep step-ca vulnerabilities

Cisco Talos' Vulnerability Discovery & Research team recently disclosed vulnerabilities in Biosig Project Libbiosig, Grassroot DiCoM, and Smallstep step-ca. The vulnerabilities mentioned in this blog post have been patched by their respective vendors, all in adherence to Cisco 's third-party...

UAT-9686 actively targets Cisco Secure Email Gateway and Secure Email and Web Manager

Cisco Talos recently discovered a campaign targeting Cisco AsyncOS Software for Cisco Secure Email Gateway, formerly known as Cisco Email Security Appliance ESA, and Cisco Secure Email and Web Manager, formerly known as Cisco Content Security Management Appliance SMA. We assess with moderate...

Lexi DiScola’s guide to global teamwork and overflowing TBRs

Welcome back to Humans of Talos. This month, Amy chats with Senior Cyber Threat Analyst Lexi DiScola from the Strategic Analysis team. Lexi's journey into cybersecurity is anything but traditional -- she brings a background in political science and French to her work tracking global cyber threats...

One newsletter to rule them all

Welcome to this week's edition of the Threat Source newsletter. " It's a dangerous business, going out your door. You step onto the road, and if you don't keep your feet, there's no knowing where you might be swept off to." -- Bilbo Baggins It's almost the end of the year, which feels like the...

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

The Patch Tuesday for December of 2025 includes 57 vulnerabilities, including two that Microsoft marked as "critical." The remaining vulnerabilities listed are classified as "important." Microsoft assessed that exploitation of the two "critical" vulnerabilities is "less likely." CVE ‑2025‑62562 i...

New BYOVD loader behind DeadLock ransomware attack

While tracking ransomware activities, Cisco Talos uncovered new tactics, techniques, and procedures TTPs linked to a financially motivated threat actor targeting victims with DeadLock ransomware. The actor used the Bring Your Own Vulnerable Driver BYOVD technique with a previously unknown loader ...

New in Snort3: Enhanced rule grouping for greater flexibility and control

Today, Cisco Talos is introducing new capabilities for Snort3 users within Cisco Secure Firewall. These enhancements are designed to give you greater flexibility in how you manage, organize, and prioritize detection rules. They also make it easier to align SNORT® rules with your organization's...

Socomec DIRIS Digiware M series and Easy Config, PDF XChange Editor vulnerabilities

Cisco Talos' Vulnerability Discovery & Research team recently disclosed an out-of-bounds read vulnerability in PDF XChange Editor, and ten vulnerabilities in Socomec DIRIS Digiware M series and Easy Config products. The vulnerabilities mentioned in this blog post have been patched by their...

Your year-end infosec wrapped

Welcome to this week's edition of the Threat Source newsletter. " They say that a person's personality is the sum of their experiences. But that isn't true, at least not entirely, because if our past was all that defined us, we'd never be able to put up with ourselves. We need to be allowed to...

Spy vs. spy: How GenAI is powering defenders and attackers

Generative AI GenAI is reshaping cybersecurity for both attackers and defenders, but its future capabilities are difficult to measure as techniques and models are evolving rapidly. Adversaries continue to use GenAI with varying levels of reliance. State-sponsored groups continue to take advantage...

Dell ControlVault, Lasso, GL.iNet vulnerabilities

Cisco Talos' Vulnerability Discovery & Research team recently disclosed five vulnerabilities in Dell ControlVault 3 firmware and its associated Windows software, four vulnerabilities in Entr'ouvert Lasso, and one vulnerability in GL.iNet Slate AX. The vulnerabilities mentioned in this blog post...

Care that you share

Welcome to this week's edition of the Threat Source newsletter. Back in April, I wrote about the risks of unintentionally leaking information while using search engines. Since then, I've been thinking: Life doesn't just happen in front of a keyboard. There's a social side, too or so I'm told. Wit...

It’s not personal, it’s just business

Welcome to this week's edition of the Threat Source newsletter. This week, we explore how advances in agentic AI are rapidly transforming the cyber crime business. Agentic AI programming gives AI agents autonomy, allowing them to interact with external systems to collect information, make decisio...

Bill Largent: On epic reads, lifelong learning, and empathy

Welcome to another episode of Humans of Talos! This week, Amy sits down with William Bill Largent from the Strategic Planning and Communications team. Bill's role as Senior Security Researcher spans from threat research to communicating Talos's critical work to internal teams, partners, and...

Viasat and the terrible, horrible, no good, very bad day

Welcome to this week's edition of the Threat Source newsletter. A year ago, fresh off a layoff, I never would have guessed I'd be spending Halloween weekend bouncing between conversations about space policy, satellite hacking, and wedding plans. That's exactly what happened when my space analyst...

Unleashing the Kraken ransomware group

In August 2025, Cisco Talos observed big-game hunting and double extortion attacks carried out by Kraken, a Russian-speaking group that has emerged from the remnants of the HelloKitty ransomware cartel. Talos observed in one intrusion that the Kraken actor exploited Server Message Block SMB...

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

Microsoft has released its monthly security update for November 2025, which includes 63 vulnerabilities affecting a range of products, including 5 that Microsoft marked as "critical." Current intelligence shows that one of the important vulnerabilities, CVE-2025-62215, has already been detected i...

Remember, remember the fifth of November

Welcome to this week's edition of the Threat Source newsletter. Ever heard the phrase in this week's title? For our non-British readers, here's the quick version: Every year on November 5, people across the U.K. gather for bonfires, sparklers, fireworks, and attempting to literally handle a hot...

Do robots dream of secure networking? Teaching cybersecurity to AI systems

This blog explores how to equip autonomous AI agents with cybersecurity knowledge, enabling them to make informed decisions about internet safety, such as identifying trustworthy links and websites. It demonstrates a proof of concept using LangChain and OpenAI, integrated with the Cisco Umbrella...

TruffleHog, Fade In and BSAFE Crypto-C vulnerabilities

Cisco Talos' Vulnerability Discovery & Research team recently disclosed three vulnerabilities in Dell BSAFE, two in Fade In screenwriting software, and one in Trufflehog. The vulnerabilities mentioned in this blog post have been patched by their respective vendors, all in adherence to Cisco 's...

Trick, treat, repeat

Welcome to this week's edition of the Threat Source newsletter. This one is pretty much an updated, Halloween-themed version of my newsletter from July, including data up through Q3. October 14th has passed, so free support for Windows 10 has come to an end, leaving you with no more fixes unless...

Dynamic binary instrumentation (DBI) with DynamoRio

This blog introduces dynamic binary instrumentation DBI and guides you through building your own DBI tool with the open-source DynamoRIO framework on Windows 11. DBI enables powerful runtime analysis and modification of binaries critical for malware analysis, security auditing, reverse engineerin...

Cybersecurity on a budget: Strategies for an economic downturn

During economic uncertainty, businesses face the challenge of maintaining strong cybersecurity while managing tightened budgets. Cyber threats can become more numerous, motivated, and persistent during economic downturns, making the need for resilient, cost-effective security measures critical...

Uncovering Qilin attack methods exposed through multiple cases

In the second half of 2025, the ransomware group Qilin has continued to publish victim information on its leak site at a pace of more than 40 cases per month, making it one of the most impactful ransomware groups worldwide. The manufacturing sector has been the most affected, followed by...

Think passwordless is too complicated? Let's clear that up

By Janet Ho, Cisco Duo Why passwords are still a problem We've relied on passwords for years to protect our online accounts, but they've also become one of the easiest ways attackers get in. Many people reuse or simplify passwords, or even write them down because it's hard to remember so many. Th...

Strings in the maze: Finding hidden strengths and gaps in your team

Welcome to this week's edition of the Threat Source newsletter. "The truth about the world, he said, is that anything is possible... For existence has its own order and that no man's mind can compass, that mind itself being but a fact among others." ― Cormac McCarthy, "Blood Meridian" Earlier thi...

IR Trends Q3 2025: ToolShell attacks dominate, highlighting criticality of segmentation and rapid response

Threat actors predominately exploited public-facing applications for initial access this quarter, with this tactic appearing in over 60 percent of Cisco Talos Incident Response Talos IR engagements - a notable increase from less than 10 percent last quarter. This spike is largely attributable to ...

Reducing abuse of Microsoft 365 Exchange Online’s Direct Send

Overview Microsoft 365 Exchange Online's Direct Send is designed to solve an enterprise-scale operational challenge: certain devices and legacy applications such as multifunction printers, scanners, building systems, and older line‑of‑business apps, need to send email into the tenant but lack the...