CVE-2026-20131

Analyzed

Published: 04 Mar 2026, 17:17

Last modified:19 Mar 2026, 16:20

Vulnerability Summary

Overall Risk (default)

high

70/100

CVSS Score

10 CRITICAL

v3.1 (cve.org)

EPSS Score

0.57% LOW

1% probability 0.00%

KEV

Listed

CISA

1 listing

Ransomware

Known Use

Public exploits

None found

Dark Web

Not detected

Timeline

04 Mar 2026, 17:17

Published

Vulnerability first disclosed

19 Mar 2026, 00:00

Added to CISA KEV

Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management Deserialization of Untrusted Data Vulnerability

19 Mar 2026, 16:20

Last Modified

Vulnerability information updated

22 Mar 2026, 00:00

CISA Remediation Due

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Description

A vulnerability in the web-based management interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to execute arbitrary Java code as root on an affected device. This vulnerability is due to insecure deserialization of a user-supplied Java byte stream. An attacker could exploit this vulnerability by sending a crafted serialized Java object to the web-based management interface of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the device and elevate privileges to root. Note: If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.

CVSS Metrics

v3.1•CRITICAL•Score: 10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

EPSS Trends

Current EPSS score: 0.57%• Percentile: 68%

Techniques & Countermeasures

CWE-502•Deserialization of Untrusted Data
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

Affected Systems

cisco•cisco secure firewall management center (fmc)
6.4.0.13 | 6.4.0.14 | 6.4.0.15 | 6.4.0.16 | 6.4.0.17 | 6.4.0.18 | 7.0.0 | 7.0.0.1 | 7.0.1 | 7.0.1.1 | 7.0.2 | 7.0.2.1 | 7.0.3 | 7.0.4 | 7.0.5 | 7.0.6 | 7.0.6.1 | 7.0.6.2 | 7.0.6.3 | 7.0.7 | 7.0.8 | 7.0.8.1 | 7.1.0 | 7.1.0.1 | 7.1.0.2 | 7.1.0.3 | 7.2.0 | 7.2.1 | 7.2.2 | 7.2.0.1 | 7.2.3 | 7.2.3.1 | 7.2.4 | 7.2.4.1 | 7.2.5 | 7.2.5.1 | 7.2.6 | 7.2.7 | 7.2.5.2 | 7.2.8 | 7.2.8.1 | 7.2.9 | 7.2.10 | 7.2.10.2 | 7.2.10.1 | 7.3.0 | 7.3.1 | 7.3.1.1 | 7.3.1.2 | 7.4.0 | 7.4.1 | 7.4.1.1 | 7.4.2 | 7.4.2.1 | 7.4.2.2 | 7.4.2.3 | 7.4.2.4 | 7.4.3 | 7.4.4 | 7.4.5 | 7.6.0 | 7.6.1 | 7.6.2 | 7.6.2.1 | 7.6.3 | 7.6.4 | 7.7.0 | 7.7.10 | 7.7.10.1 | 7.7.11 | 10.0.0
cisco•secure_firewall_management_center
6.4.0.13 | 6.4.0.14 | 6.4.0.15 | 6.4.0.16 | 6.4.0.17 | 6.4.0.18 | 7.0.0 | 7.0.0.1 | 7.0.1 | 7.0.1.1 | 7.0.2 | 7.0.2.1 | 7.0.3 | 7.0.4 | 7.0.5 | 7.0.6 | 7.0.6.1 | 7.0.6.2 | 7.0.6.3 | 7.0.7 | 7.0.8 | 7.0.8.1 | 7.1.0 | 7.1.0.1 | 7.1.0.2 | 7.1.0.3 | 7.2.0 | 7.2.0.1 | 7.2.1 | 7.2.2 | 7.2.3 | 7.2.3.1 | 7.2.4 | 7.2.4.1 | 7.2.5 | 7.2.5.1 | 7.2.5.2 | 7.2.6 | 7.2.7 | 7.2.8 | 7.2.8.1 | 7.2.9 | 7.2.10 | 7.2.10.1 | 7.2.10.2 | 7.3.0 | 7.3.1 | 7.3.1.1 | 7.3.1.2 | 7.4.0 | 7.4.1 | 7.4.1.1 | 7.4.2 | 7.4.2.1 | 7.4.2.2 | 7.4.2.3 | 7.4.2.4 | 7.4.3 | 7.4.4 | 7.4.5 | 7.6.0 | 7.6.1 | 7.6.2 | 7.6.2.1 | 7.6.3 | 7.6.4 | 7.7.0 | 7.7.10 | 7.7.10.1 | 7.7.11 | 10.0.0