Actively exploited in the wild
Cisco Secure Firewall Management Center Use of Hard-coded Password Vulnerability
Cisco - Secure Firewall Management Center (FMC) · Listed in the CISA KEV since 2026-07-29. This indicates confirmed attacks in production environments.
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.
CVE-2026-20316
MediumCVSS 5.3KEVExploitation Probability (EPSS)
Elevated risk53th percentile - higher than 53% of all known CVEs
Summary
The web interface of Cisco Secure Firewall Management Center (FMC) contains static credentials for a low-privileged account, allowing an unauthenticated remote attacker to log in and access sensitive data. This vulnerability can be chained with other flaws for privilege escalation.
Risk Assessment
An attacker can access sensitive configuration data and logs, and combined with other vulnerabilities, gain full control of the device.
Recommendation
Change the default password for the low-privileged account and restrict management interface access to trusted networks only.
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Original NVD description (English source)
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.

