Vulnerability in Cisco Secure Firewall Management Center (Fmc)

CVE-2026-20316

A vulnerability in the web interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to log in to an affected device using a low-privileged account to access sensitive data within the impacted systems. This vulnerability is due to the presence of static user credentials for a low-privileged account. An attacker could exploit this vulnerability by using the account to log in to an affected system. A successful exploit could allow the attacker to log in to the affected system and access sensitive data as the low-privileged user.  Note: If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.   Cisco has assigned this security advisory a Security Impact Rating (SIR) of High rather than Medium as the score indicates. The reason is that this vulnerability can be used with other Cisco Secure FMC Software vulnerabilities to elevate privileges.

EPSS: 0.112 (95.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

Affected products

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: .

Required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Known ransomware campaign use: yes.

References

Frequently asked questions

What is CVE-2026-20316?
CVE-2026-20316 is a medium-severity vulnerability in Cisco Secure Firewall Management Center (Fmc), classified under Use of Hard-coded Password. CVSS score: 5.3/10. Published 2026-07-29.
How severe is CVE-2026-20316?
Medium severity. CVSS v3 base score is 5.3 out of 10.
Is CVE-2026-20316 known to be exploited?
Yes. CVE-2026-20316 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-07-29), indicating it is being actively exploited.