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CiscoCVE-2026-20343

Cisco Secure Firewall Management Center (FMC): denial of service

High7.5CVE-2026-20343 · Published Sep 16, 2026 · updated Sep 18, 2026

A vulnerability in a critical API for Cisco Secure FMC Software could allow an unauthenticated, remote attacker to download sensitive files and use unbounded disk space. This vulnerability exists because a critical API lacks authentication. An attacker could exploit this vulnerability by repeatedly invoking the API. A successful exploit could allow the attacker to download sensitive files that should be restricted and consume disk space so the device could become unresponsive, causing a DoS condition.

Cisco advisory

Affected versions

PackageAffectedFixed in
Cisco Secure Firewall Management Center (FMC)
Product
<= 7.3.0No fix yet
<= 7.3.1No fix yet
<= 7.3.1.1No fix yet
<= 7.4.0No fix yet
Details and references

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