Actively exploited
Listed in CISA’s Known Exploited Vulnerabilities catalog since March 19, 2026.
CVE-2026-20131
Secure Firewall Management Center (FMC) vulnerability
Added to KEV March 19, 2026
Alert details
- Source feed
- CISA KEV
- CVE ID
- CVE-2026-20131
- CWE
- CWE-502
- Affected products
- Secure Firewall Management Center (FMC) · Cisco Secure Firewall Management Center (FMC) · Cisco
What happened
Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management contain a deserialization of untrusted data vulnerability in the web-based management interface that could allow an unauthenticated, remote attacker to execute arbitrary Java code as root on an affected device.
What it means for your business
Cisco Secure Firewall Management Center (FMC) is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2026-20131). Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management contain a deserialization of untrusted data vulnerability in the web-based management interface that could allow an unauthenticated, remote attacker to execute arbitrary Java code as root on an affected device. CISA remediation due date: 2026-03-22. If you need help checking exposure, call (864) 335-9223.
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
CISA due date: March 22, 2026
Sources
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