Cisco FMC Flaws Exploited to Steal Credentials and Deploy Qilin Ransomware  Ravie Lakshmanan  Sep 11, 2026 Vulnerability / Malware Cisco has revealed that three distinct threat clusters linked to ransomware and state-sponsored attacks have been exploiting two recently patched Secure Firewall Management Center (FMC) vulnerabilities. The attacks leverage CVE-2026-20079 (CVSS score: 10.0), an authentication bypass vulnerability in the web interface of FMC software that could allow an unauthenticated, remote attacker to bypass authentication and execute script files on an affected device to obtain root access to the underlying operating system. The second flaw under exploitation is CVE-2026-20316 (CVSS score: 5.3), which could allow an unauthenticated, remote attacker to log in to an affected device using a low-privilege account to access sensitive data within susceptible systems. It can be paired with other Cisco Secure FMC vulnerabilities to elevate privileges. Cisco Talos said it identified three clusters of post-compromise activity of FMC instances associated with state-sponsored and crimeware threat actors. These include - UAT-12197 , which has exploited CVE-2026-20079 to deploy JSP-based web shells and a Java Archive (JAR)-based command executor to query internal databases and obtain user authentication data and credentials UAT-11823 , which has exploited both CVE-2026-20079 and CVE-2026-20316 to deliver a Netcat-based reverse shell, two bash scripts to harvest managed-device configurations, and a variant of Cyclops Blink , a modular ELF implant previously attributed to the Russian state-sponsored hacking group Sandworm UAT-11988 , a ransomware operation that has exploited CVE-2026-20316 for initial access and then used legitimate built-in FMC tooling as part of a living-off-the-land (LotL) attack to conduct extensive reconnaissance of the victim's environment, drop tunneling tools to maintain network access, collect credentials, build a target list of endpoints to encrypt, terminate security tools, and deploy Qilin ransomware on selected systems. "Customers are strongly advised to apply hotfixes for affected software versions already released by Cisco for CVE-2026-20079 and CVE-2026-20316," Cisco said, adding it intends to ship a comprehensive hardening release for various internally discovered vulnerabilities next week. The development comes as the U.S. Cybersecurity and Infrastructure Security Agency (CISA) added CVE-2026-20079 to its Known Exploited Vulnerabilities (KEV) catalog, requiring Federal Civilian Executive Branch (FCEB) agencies to apply the patches by September 12, 2026. The second vulnerability, CVE-2026-20316, was added to the KEV catalog in late July 2026. Found this article interesting? Follow us on Google News , Twitter and LinkedIn to read more exclusive content we post. SHARE      Tweet  Share  Share  Share   Share on Facebook  Share on Twitter  Share on Linkedin  Share on Reddit  Share on Hacker News  Share on Email  Share on WhatsApp Share on Facebook Messenger  Share on Telegram SHARE  cisco , Malware , Nation-State , network security , ransomware , Vulnerability ⚡ Top Stories This Week Attackers Exploit Critical Langflow and Rails Flaws in Credential-Probing and C2 Activity Iranian Hackers Pose as Recruiters to Deliver Cross-Platform RATs Through Coding Tests ⚡ Weekly Recap: Chrome 0-Day, Router Hijacks, Coder Supply Chain Attack and More N-able Issues Fourth N-central Hotfix in Five Weeks for Unauthenticated RCE Flaw Attackers Hijack MikroTik Routers Through Internet-Exposed SSH Without Authentication Unpatched Magento and Adobe Commerce Zero-Day Exploited to Backdoor Online Stores Attackers Breached JetBrains Cadence via Unpatched TeamCity, Extracting AWS Credentials Critical VMware Workstation and Fusion Flaw Lets VM Admins Execute Host Code Thousands of OpenAI Agents Quietly Turned an Abandoned Wiki Into Their Coordination Channel Attackers Exploit PaperCut Flaws to Steal Credentials From Schools and Universities Phishing Campaign Sends Millions of Emails Using Invisible Unicode to Evade Filters PostgreSQL Fixes 12-Year-Old Logical Decoding Flaw Enabling Replication-Role Code Execution New Ted Backdoor Hides Inside Victims' Own HAProxy Builds to Intercept Web Traffic Google Releases Chrome Update to Patch Actively Exploited V8 Zero-Day ThreatsDay: CEO Phishing Kits, 5K Dropbox Account Hacks, OAuth Traps + 17 More Stories Critical Cisco Nexus 9000 Flaw Lets Unauthenticated Remote Attackers Run Code as Root Thomson Reuters Court Software Breach May Have Exposed SSNs and Sealed Data Pegasus Zero-Click Spyware Exploit Infects Serbian Student Movement Member's iPhone Researcher Releases FalconFlank PoC Showing Privilege Escalation in CrowdStrike Falcon Fake Software Installers Disable Windows Update and Weaken Microsoft Defender Malicious .git Configs Can Make Claude, Codex, Cursor, and Other AI Agents Run Attacker Code Meta Ads Push StreamRat Android Trojan That Can Gain Near-Complete Device Control Attackers Exploit Two SonicWall SMA 1000 Zero-Days That May Form an Attack Chain GeoNetwork Fixes Unauthenticated RCE Chain Affecting Government Geoportal Backends Researchers Use Claude to Port Pre-Auth RCE Exploit From One PLC Model to Another ⭐ Featured Resources Get the eBook: Map Enterprise AI Risk Across the Full Lifecycle Give SOC Analysts Visibility Into 90% of Attacks Within 60 Seconds Benchmark Your SOC's AI Adoption With the 2026 Security Operations Report Register for LDR516: Strategic Vulnerability and Threat Management at SANS DC Metro