Cisco Talos Blog

Cisco Talos is actively tracking the exploitation of two vulnerabilities in Cisco’s Secure Firewall Management Center (FMC) Software. First, CVE-2026-20079 is an authentication bypass vulnerability in unpatched instances of Cisco’s Secure FMC Software, which allows an unauthenticated, remote attacker to bypass authentications and execute scripts on impacted devices to obtain root access to the underlying operating system.

Microsoft has released its monthly security update for September 2026, which includes 973 vulnerabilities affecting a range of products, including 113 that Microsoft marked as "critical." Microsoft notes that 2 of the vulnerabilities disclosed this month have been exploited in the wild: CVE-2026-81963 affects Windows Update Stack.

Cisco Talos began an investigation after observing a DLL named "verification.google" executing from WebDAV at a Ukrainian government organization. We assess with moderate confidence that the attacks are not targeted at a particular organization, but are a part of a cryptocurrency and credentials-stealing operation using the Amatera stealer as the primary payload.

Cisco Talos is tracking a cryptocurrency-stealing campaign that abuses the Google Visualization API for command and control (C2), retrieving obfuscated JavaScript from a publicly published Google Sheets document and injecting it into the victim's browser session. The actors use a variation on ClickFix social engineering.

Welcome to this week’s edition of the Threat Source newsletter. Our goal is to get accurate threat intelligence to our audience as quickly as possible, with all the context you need to ask the right questions of your own environment: How at risk are we from this threat? Are we prepared for it? And what can we do about it? What you don’t often see is all the... well, frankly, “mess” involved in producing it. All the dead ends we followed until we could confirm those ends were as dead as a doornail.

Welcome to this week’s edition of the Threat Source newsletter. Hello, everyone. Long time reader, first time writer here at the Threat Source newsletter! I wanted to start out by introducing myself.

We open a JavaScript artifact hoping for code, and instead get string arrays, strangely named functions, encoded URLs, runtime decoders, and eval statements. That is the point where “reading the script” stops being enough. Obfuscated JavaScript is still code, but it is code with the useful context stripped out, the names ruined, the strings hidden, and the real behavior pushed into runtime.

Selecting a model for your security operations center (SOC) and digital forensics and incident response (DFIR) tasks is important, but selecting the best one is more involved than you might think. SOC tasks rely on a combination of model efficacy, analysis time, cost, and consistency of results. Cisco Talos tested 66 model and reasoning combinations across offerings from both Anthropic and OpenAI on a log analysis task to see if we could identify a clear winner.

As frontier models advance in cyber capability, their guardrails also become more restrictive. Defenders relying on these models to power core SOC processes cannot afford to pay the “safety penalty” of being blocked by these safeguards. Organizations should monitor model refusal rates and use the data to create a strategy to ensure operational sovereignty. The allure of the cloud and the hidden "safety penalty" Cybersecurity has made a big bet on cloud-hosted AI.

Welcome to this week’s edition of the Threat Source newsletter. Hello friend. I’m Mick. This is my first Threat Source newsletter, so I should probably introduce myself before I start telling you all the things I think you should be paying attention to. With assistance from an unnamed LLM, my bio reads like this: Mick Baccio is a globally recognized security strategist with a career spanning offensive operations, threat intelligence, and national-level incident response.