CVE-2026-20079 — newly added to CISA KEV

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.&nbs

01What CISA says about this vulnerability

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. 

02Required action — verbatim from CISA

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

03Notes & references

• sec.cloudapps.cisco.com — https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/ci…
• seclists.org — http://seclists.org/fulldisclosure/2026/Aug/80
• blog.talosintelligence.com — https://blog.talosintelligence.com/fmc-ongoing-exploitation/
• www.cisa.gov — https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-…

04SARA's analyst layer — why this matters

This vulnerability is currently on the CISA KEV list, which CISA only adds CVEs to when there is reliable evidence of active exploitation in the wild. For federal civilian agencies, BOD 22-01 requires remediation by the due date above. For everyone else, KEV is the strongest "patch immediately" signal you can get from public threat intel.

05Affected products (summary)

No structured affected-product list available — see references below for vendor advisories.

06Detection

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