CVE-2026-20079

CRITICALCVSS 10.0Known Exploited

CISA Known Exploited Vulnerability

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-20079

Remediation deadline: September 12, 2026

Description

Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management contain an authentication Bypass using an alternate path or channel vulnerability 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.

Timeline

Published:March 4th, 2026 6:16 PM

Last modified:July 29th, 2026 5:16 PM

Added to KEV:September 9th, 2026

CVSS Scoring

CVSS v3: 10.0 (CRITICAL)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Weaknesses (CWE)

CWE-288

References & Reports

Advisories, patches, and third-party reports

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2

Source: NIST NVD · Data may lag official sources by up to one minute