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...

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 ...

Defining a new methodology for modeling and tracking compartmentalized threats

In the evolving cyberthreat landscape, Cisco Talos is witnessing a significant shift towards compartmentalized attack kill chains, where distinct stages -- such as initial compromise and subsequent exploitation -- are executed by multiple threat actors. This trend complicates traditional threat...

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...

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...

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...

"There is no business school class that would ever sit down and design Talos"

As part of the celebrations of Cisco Talos turning 10, wed like to take you back to where it all began: How we formed our mission of protecting our customers and making the internet suck a bit less, an insight into our culture, and how we came to work with some of the most talented human beings o...

Hidden between the tags: Insights into spammers’ evasion techniques in HTML Smuggling

Cisco Talos has spotted several malicious email campaigns over the past few months that disguise JavaScript code within HTML email attachments, a technique commonly known as "HTML Smuggling." Cisco Talos has noticed that some industry verticals were targeted more than others by email threats usin...

Why Apple added protection against quantum computing when quantum computing doesn’t even exist yet

Apple released a new update for nearly all its devices that provides an all-new type of encryption for its iMessages to the point that, in theory, iMessages are now protected against attacks from quantum computers. This is a little tricky because, as weve covered before, quantum computers dont...

TinyTurla-NG in-depth tooling and command and control analysis

Cisco Talos, in cooperation with CERT.NGO, has discovered new malicious components used by the Turla APT. New findings from Talos illustrate the inner workings of the command and control C2 scripts deployed on the compromised WordPress servers utilized in the compromise we previously disclosed...

Qakbot-affiliated actors distribute Ransom Knight malware despite infrastructure takedown

The threat actors behind the Qakbot malware have been conducting a campaign since early August 2023 in which they have been distributing Ransom Knight ransomware and the Remcos backdoor via phishing emails. Notably, this activity appeared to begin before the FBI seized Qakbot infrastructure in la...

Threat Roundup for September 22 to September 29

Today, Talos is publishing a glimpse into the most prevalent threats weve observed between Sept. 22 and Sept. 29. As with previous roundups, this post isnt meant to be an in-depth analysis. Instead, this post will summarize the threats weve observed by highlighting key behavioral characteristics,...

A secondhand account of the worst possible timing for a scammer to strike

Welcome to this weeks edition of the Threat Source newsletter. Up until last week, I had never considered the timing of a scam to be important. Im so used to just swiping away emails or text messages at random times during the day that Id never considered what would happen if an adversary happene...

Code leaks are causing an influx of new ransomware actors

Ransomware gangs are consistently rebranding or merging with other groups, as highlighted in our 2022 Year in Review, or these actors work for multiple ransomware-as-a-service RaaS outfits at a time, and new groups are always emerging. This trend is already continuing this year. Since 2021, there...

What might authentication attacks look like in a phishing-resistant future?

By Thorsten Rosendahl and Tiago Pereira, with contributions from Matthew Miller. The industry has come a long way in terms of improving how we make user authentication more secure. From the most basic concept of relying on usernames and passwords for authentication to enabling multi-factor...

How Joe Marshall helps defend everything from electrical grids to grain co-ops across multiple continents

Joe Marshall was a security practitioner before he even knew it. Marshall started his career in information technology as a systems administrator. On the surface, he jokes that he was a "white-collar plumber" -- fixing IT issues as they arose, handing out new credentials and asking users if they...

Fighting the Good Fight: Life inside the Talos Ukraine Task Unit

As we spoke about in the new ThreatWise TV documentary, "People Matter: A look back on how Cisco Talos has been supporting Ukraine," war isnt something that often appears in an organizations business continuity or disaster recovery plans. In the months leading up to Russias invasion of Ukraine,...

APT Topic Summary Report: Cisco Talos Year in Review 2022

State-sponsored or state-aligned advanced persistent threats APTs adapted to the changing geopolitical landscape in 2022. Cisco Talos observed several offensive cyber campaigns linked to several groups stemming from Russia, Iran, China, North Korea, and countries in the Indian subcontinent. These...

Emotet coming in hot

Emotet is a ubiquitous and well-known banking trojan that has evolved over the years to become a very successful modular botnet capable of dropping a variety of other threats. Even after a global takedown campaign in early 2021 disrupted the botnet, it reemerged later that year, rebuilding its...

Threat Source newsletter (Sept. 29, 2022) — Personal health apps are currently under a spotlight, but their warning signs have always been there

By Jon Munshaw. Welcome to this week’s edition of the Threat Source newsletter. I’ve spent the past few months with my colleague Ashlee Benge looking at personal health apps’ privacy policies. We found several instances of apps that carry sensitive information stating they would share certain...

Multiple ransomware data leak sites experience DDoS attacks, facing intermittent outages and connectivity issues

By Azim Khodjibaev, Colin Grady, Paul Eubanks. Since Aug. 20, 2022, Cisco Talos has been monitoring suspected distributed denial-of-service DDoS attacks resulting in intermittent downtime and outages affecting several ransomware-as-a-service RaaS data leak sites. While the source and origin of th...

Vulnerability Spotlight: Command injection vulnerabilities in Robustel cellular router

Francesco Benvenuto of Cisco Talos discovered these vulnerabilities. Blog by Jon Munshaw. Cisco Talos recently discovered four vulnerabilities in the Robustel R1510 industrial cellular router. The R1510 is a portable router that shares 2G, 3G and 4G wireless internet access. It comes... This is...

From BlackMatter to BlackCat: Analyzing two attacks from one affiliate

By Tiago Pereira with contributions from Caitlin Huey. BlackCat is a recent and growing ransomware-as-a-service RaaS group that targeted several organizations worldwide over the past few months.There are rumors of a relationship between BlackCat and the BlackMatter/DarkSide ransomware groups,...

Threat Roundup for October 29 to November 5

Today, Talos is publishing a glimpse into the most prevalent threats we've observed between Oct. 29 and Nov. 5. 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...

Microsoft Exchange vulnerabilities exploited once again for ransomware, this time with Babuk

By Chetan Raghuprasad and Vanja Svajcer, with contributions from Caitlin Huey. Cisco Talos recently discovered a malicious campaign deploying variants of the Babuk ransomware predominantly affecting users in the U.S. with smaller number of infections in U.K., Germany, Ukraine, Finland, Brazil,...

Microsoft Patch Tuesday for Sept. 2021 — Snort rules and prominent vulnerabilities

By Jon Munshaw, with contributions from Holger Unterbrink. Microsoft released its monthly security update Tuesday, disclosing 85 vulnerabilities across the company’s firmware and software. This month’s release is headlined by an official patch for the critical remote code execution... This is onl...

Threat Source newsletter (Aug. 26, 2021)

Newsletter compiled by Jon Munshaw.Good afternoon, Talos readers. We have RATs on RATs on RATs over the past few weeks. And last week, we found a few more heading to Latin America to target users and try to steal their login credentials. The threat actor in this case has some compelling... This i...

Microsoft Patch Tuesday for August 2021 — Snort rules and prominent vulnerabilities

By Jon Munshaw, with contributions from Martin Lee. Microsoft released its monthly security update Tuesday, disclosing 44 vulnerabilities in the company’s firmware and software. This is the fewest amount of vulnerabilities Microsoft has patched in a month in more than two years. There... This is...

Beers with Talos, Ep. #108: Kaseya it ain't so

Beers with Talos BWT Podcast episode No. 108 is now available. Download this episode and subscribe to Beers with Talos:Apple Podcasts Google PodcastsSpotify StitcherIf iTunes and Google Play aren't your thing, click here. Who needed a summer vacation anyway? The whole Beers... This is only the...

Vulnerability Spotlight: Use-after-free vulnerability in Foxit PDF Reader

Aleksandar Nikolic of Cisco Talos discovered this vulnerability. Blog by Jon Munshaw. Cisco Talos recently discovered a use-after-free vulnerability in the Foxit PDF Reader. Foxit PDF Reader is one of the most popular PDF document readers currently available. As a complete... This is only the...

Threat Roundup for February 26 to March 5

Today, Talos is publishing a glimpse into the most prevalent threats we've observed between Feb. 26 and March 5. 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...

Vulnerability Spotlight: Out-of-bounds read vulnerability in Slic3r could lead to information disclosure

Lilith of Cisco Talos discovered this vulnerability. Blog by Jon Munshaw. Cisco Talos recently discovered an out-of-bounds read vulnerability in Slic3r's library. Slic3r is an open-source 3-D printing toolbox, mainly utilized for translating assorted 3-D printing model file types into machine cod...

Threat Roundup for February 12 to February 19

Today, Talos is publishing a glimpse into the most prevalent threats we've observed between Feb. 12 and Feb. 19. 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...

Vulnerability Spotlight: Allen-Bradley Flex I/O vulnerable to denial of service

Jared Rittle of Cisco Talos discovered this vulnerability. Blog by Jon Munshaw. The Rockwell Automation Allen-Bradley Flex I/O input/output device is vulnerable to a denial-of-service vulnerability. FLEX I/O provides a wide range of input/output operations while keeping a smaller form factor. Use...

Threat Source newsletter for July 30, 2020

Newsletter compiled by Jon Munshaw. Good afternoon, Talos readers. Adversaries love to use headlines as part of their spam campaigns. From COVID-19, to Black Lives Matter and even Black Friday every year, the bad guys are wanting to capitalize on current events. Why is this the case, and when do...

Microsoft Patch Tuesday for June 2020 — Snort rules and prominent vulnerabilities

By Jon Munshaw. Microsoft released its monthly security update Tuesday, disclosing more than 120 vulnerabilities across its array of products. While none of the vulnerabilities disclosed have been exploited in the wild, users of all Microsoft and Windows products are urged to update their softwar...

Vulnerability Spotlight: Code execution vulnerability in Microsoft Excel

Marcin “Icewall” Noga of Cisco Talos discovered this vulnerability. Blog by Jon Munshaw. Cisco Talos recently discovered a code execution vulnerability in some versions of Microsoft Excel. An attacker could exploit this vulnerability by tricking the victim into opening a specially crafted Excel...

Threat Source (April 18): New attacks distribute Formbook, LokiBot

Newsletter compiled by Jonathan Munshaw. Welcome to this week’s Threat Source newsletter — the perfect place to get caught up on all things Talos from the past week. If you haven’t yet, there’s still time to register for this year’s Talos Threat Research Summit — our second annual conference by...

Beers with Talos Ep. #51: Sea Turtles yeeting packets

Beers with Talos BWT Podcast Ep. No. 51 is now available. Download this episode and subscribe to Beers with Talos: If iTunes and Google Play aren't your thing, click here. Recorded April 12, 2019 — Today, we rip through a few other things to spend most of our time discussing Sea Turtle, the lates...

Threat Roundup for July 6-13

Today, as we do every week, Talos is giving you a glimpse into the most prevalent threats we've observed this week — covering the dates between July 6 and 13. 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 ...

SamSam - The Evolution Continues Netting Over $325,000 in 4 Weeks

This post was written by Vitor Ventura Introduction Talos has been working in conjunction with Cisco IR Services on what we believe to be a new variant of the SamSam ransomware. This ransomware has been observed across multiple industries including Government, Healthcare and ICS. These attacks do...

Beers with Talos EP 15: Landing a Job, Phishing Midstream, and Paul’s IDA Palette

Beers with Talos BWT Podcast Episode 15 is now available. Download this episode and subscribe to Beers with Talos:img border="0" data-original-height="45" data-original-width="160" src="https://2.bp.blogspot.com/-E-RSSZ9jbUY/WaWCkLGZnZI/AAAAAAAAAJE/Ciiz-Si4oA0cgR9tMGSGbT9336qr...

Threat Round-up for May 05 - May 12

Today, Talos is publishing a glimpse into the most prevalent threats we've observed between May 05 and May 12. As with previous round-ups, this post isn't meant to be an in-depth analysis. Instead, this post will summarize the threats we've observed by highlighting key behavior characteristics,...

The Hunter's Paradox: Is it time to embrace automated threat hunting?

Should we let AI run our threat hunts? The debate usually splits into two camps. One says, "Yes, obviously! The sheer scale of our security telemetry is impossible for humans to deal with." The other says, "Absolutely not! You can't trust an AI with something this important." The thing is, I thin...

Reporting from Vegas: Networking, AI, and good boys

Welcome to this week's edition of the Threat Source newsletter. Howdy friends, and hello from Cisco Live U.S., here in sunny and very hot Las Vegas! An interesting quirk of being sent to one of these events is you learn to understand your limits as a person. Cisco Live is a three-day event, and i...

Winning the cyber marathon with Tony Giandomenico

In the high-speed world of cybersecurity, the difference between a breach and a breakthrough often comes down to endurance. Tony Giandomenico, Senior Director of Product Management with Cisco Talos, joins me to discuss how he balances the intensity of leading major product launches with the...

Patch, track, repeat: The 2025 CVE retrospective

Welcome to this week's edition of the Threat Source newsletter. It's time to look back at a year that pushed the vulnerability landscape to new heights. I'll admit this retrospective is arriving a bit later than planned. With 48,196 CVEs in 2025 a stunning 132 vulnerabilities per day, the analysi...

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...

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...