Cisco Secure Firewall Management Center Authentication Bypass Remote Code Execution Vulnerability
100Vexday Risk Score
Patch now. It exploitation observed by VulnCheck and has a working public exploit.
ssvc Actcvss 10epss 75%
from disclosure to weapon167 days
Published on NVDMar 4
1st PoC+167d
metasploitMar 4
VulnCheck+189d
exploitation probability
75%top 1% of all CVEs
observed exploitation
yesVulnCheck
1 public exploit(s)
Action required by CISAfederal deadline: 2026-09-12
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.
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Affected products
Cisco · Cisco Secure Firewall Management Center (FMC)public PoCs found — 1
vulncheckvulncheck.com/xdb/c53c95f7b4efunverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
References
https://blog.talosintelligence.com/fmc-ongoing-exploitation/http://seclists.org/fulldisclosure/2026/Aug/80https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20079