Cisco Secure Firewall Management Center Software Java Deserialization Remote Code Execution Vulnerability (Cisco Cisco Secure Firewall Management Center (FMC))

CVE-2026-20242
CRITICAL 9.8

At a glance

Source
NVD
EPSS
EPSS 0.89 % · percentile 59 ()
State
PUBLISHED
Published
Updated
Assigner
cisco
NVD status
Awaiting Analysis

Description

A vulnerability in the External Database Access feature of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to execute arbitrary commands as root on an affected device. This vulnerability is due to insecure deserialization of a user-supplied Java byte stream from a host that is configured in the external database access list. An attacker could exploit this vulnerability by sending a crafted, serialized Java byte stream to a specific TCP port of an affected device. A successful exploit could allow the attacker to execute arbitrary commands on the device and elevate privileges to root. Notes: This vulnerability can be exploited only by an attacker who has control of a host in the external database access list. If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.

Weaknesses (CWE)

  • CWE-502 — Deserialization of Untrusted Data

References

Scores

VersionScoreVectorScored by
CVSS 3.1CRITICAL 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hcisco
CVSS 3.1CRITICAL 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HNVD · psirt@cisco.com (Secondary)

European references

CERT-FR advisories

Affected products

ProductVersions
Cisco · Cisco Secure Firewall Management Center (FMC)affected 7.0.0 ; affected 7.0.0.1 ; affected 7.0.1 ; affected 7.0.1.1 ; affected 7.0.2 ; affected 7.2.0

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD