CVE-2026-20079
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
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.
Added: 2026-09-09 · Due: 2026-09-12
Known ransomware use: Unknown
As of 2026-10-27
EPSS estimates exploitation probability over the next 30 days. KEV due dates apply to US federal civilian agencies. Confirm your affected versions in vendor advisories.
CWE: CWE-288 · Published: 2026-03-04T18:16:24.230 · Modified: 2026-09-16T17:17:16.340
Sources: NIST NVD, CISA KEV, FIRST EPSS. NVD and EPSS cached up to 6 hours; KEV up to 12 hours.
References and fixes
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2
- http://seclists.org/fulldisclosure/2026/Aug/80
- https://blog.talosintelligence.com/fmc-ongoing-exploitation/
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20079