Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management Deserialization of Untrusted Data Vulnerability — CVE-2026-20131

Summary

Advisory CVE-2026-20131. Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management Deserialization of… Vendor: Cisco. Source: CISA-KEV. Threat: critical. Known exploited in the wild.…

What to do

General, cautious steps (verify details in the official source):

• Prioritize patching or mitigation immediately (treat as actively risky).
• Identify affected product versions in your inventory and verify whether you are impacted.
• Apply vendor patches/updates or recommended mitigations as soon as available.
• Check logs/telemetry for indicators of compromise and suspicious activity.
• Consider temporary hardening: restrict access, reduce attack surface, and monitor aggressively.
• Read the official advisory for exact affected versions and remediation steps.

Official advisory

Read the official source

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