A vulnerability in Cisco Secure FMC Software could allow an authenticated, remote attacker to execute arbitrary commands at the root privilege… (CVE-2026-20340)
A vulnerability in Cisco Secure FMC Software could allow an authenticated, remote attacker to execute arbitrary commands at the root privilege level. This vulnerability is due to unsecured deserialization of web-management user-controlled data. An attacker could exploit this vulnerability by authenticating to the device and sending a crafted HTTP payload. A successful exploit could allow the attacker to save the crafted payload and then execute it on the underlying operating system as root. To exploit this vulnerability, the attacker must have valid credentials for a user account with at least the role of Security Analyst (read-only).
A vulnerability in Cisco Secure FMC Software could allow an authenticated, remote attacker to execute arbitrary commands at the root privilege… (CVE-2026-20340)
Description
A vulnerability in Cisco Secure FMC Software could allow an authenticated, remote attacker to execute arbitrary commands at the root privilege level. This vulnerability is due to unsecured deserialization of web-management user-controlled data. An attacker could exploit this vulnerability by authenticating to the device and sending a crafted HTTP payload. A successful exploit could allow the attacker to save the crafted payload and then execute it on the underlying operating system as root. To exploit this vulnerability, the attacker must have valid credentials for a user account with at least the role of Security Analyst (read-only).
CVSS v3.1
Score 8.8high
Weaknesses
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-xpr9-grjf-6fm6
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-20340"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6aab49a255bf5e2cf5991bf1
Added to database: 09/17/2026, 02:00:02 UTC
Last updated: 09/17/2026, 02:02:26 UTC
Views: 1
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