Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management Deserialization of Untrusted Data Vulnerability
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.
- Vendor
- Cisco
- Product
- Secure Firewall Management Center (FMC)
- CVSS
- 10.0
- EPSS (exploit probability)
- 44.4%
- Status
- kevransomware use
- CISA patch-by (BOD 22-01)
- Added to KEV
Is CVE-2026-20131 being exploited?
Yes. CISA added CVE-2026-20131 to its Known Exploited Vulnerabilities catalog on . CISA only lists a CVE when it has reliable evidence of exploitation in the wild. CISA marks it as known to be used in ransomware campaigns.
FIRST's EPSS model puts the probability of exploitation activity in the next 30 days at 44.4% (scored October 30, 2026).
- CISA KEV[ LISTED ]
- ENISA EUVD (exploited)[ — ]
- CIRCL KEV[ — ]
Catalog snapshot 2026-11-13. Full cross-catalog view: /kev-comparison
CVE-2026-20131 timeline
Every event links to its source. Catalog dates are each catalog's own; day offsets count from NVD publication. Data: JSON
What to do
CISA required actionApply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
US federal civilian agencies must remediate by (3 days after listing) under BOD 22-01. Everyone else: that deadline is a sensible upper bound, not a target. Vendor guidance and the NVD record are linked under Source above.
Other Cisco Secure Firewall Management Center (FMC) CVEs we track
| CVE / Vulnerability | Severity | CVSS | EPSS | Added to KEV |
|---|---|---|---|---|
| CVE-2026-20079 Cisco FMC Authentication Bypass Enables Root OS Accesswrite-up | [ CRITICAL ] | 10.0 | 88.7% | |
| CVE-2026-20316 Hard-coded credential in Cisco Secure FMC enables unauthenticated loginransomware usewrite-up | [ MEDIUM ] | 5.3 | 35.1% |