CVE-2026-20343: high-severity vulnerability in Cisco Secure Firewall Management Center (FMC)
Cisco Secure Firewall Management Center Software Information Disclosure and Disk Denial of Service Vulnerability
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.7%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
Cisco · Cisco Secure Firewall Management Center (FMC)Related CVEs — Cisco Secure Firewall Management Center (FMC)
In the same product, most dangerous first.
CVE-2026-20079CRITICALCisco Secure Firewall Management Center Authentication Bypass Remote Code Execution VulnerabilityEPSS 88.7%KEVCVE-2026-20131CRITICALCisco Secure Firewall Management Center Software Remote Code Execution VulnerabilityEPSS 44.4%KEVCVE-2026-20316MEDIUMCisco Secure Firewall Management Center Software Static Credential VulnerabilityEPSS 35.1%KEVCVE-2026-20242CRITICALCisco Secure Firewall Management Center Software Java Deserialization Remote Code Execution VulnerabilityEPSS 0.9%CVE-2026-20340HIGHCisco Secure Firewall Management Center Software Deserialization Arbitrary Root Command Execution VulnerabilityEPSS 0.7%CVE-2026-20324CRITICALCisco Secure Firewall Management Center sftunnel Root Arbitrary Code Exectution VulnerabilityEPSS 0.6%