Deserialization of Untrusted Data in Cisco Secure Firewall Management Center (formerly Firepower Management Center, FMC) - CVE-2026-20242
Published: September 17, 2026
Vulnerability identifier: #VU150533
CSH Severity: High
CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-20242
CWE-ID: CWE-502
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to insecure input validation when processing serialized data in the External Database Access feature. A remote attacker can pass specially crafted data to the application and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Affected software
Cisco Secure Firewall Management Center (formerly Firepower Management Center, FMC)
How to mitigate CVE-2026-20242
Install updates from vendor's website.
Cisco Secure Firewall Management Center (formerly Firepower Management Center, FMC) - addressed in versions 7.0.10, 7.2.12, 7.6.6, 7.7.13