Cisco Secure Client Secure Firewall Posture Module Privilege Escalation Vulnerability

Description

A vulnerability in the interprocess communication (IPC) channel of the Secure Firewall Posture module in Cisco Secure Client could allow an authenticated, local attacker to elevate privileges on an affected device. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a series of crafted IPC messages to a local socket. A successful exploit could allow the attacker to perform limited file write operations on the filesystem with SYSTEM or root privileges. Although this vulnerability affects the Secure Firewall Posture module in Cisco Secure Client on Windows, macOS, and Linux operating systems, this vulnerability could be used to obtain full root privileges on macOS and Linux. For that reason Cisco has assigned this security advisory a Security Impact Rating (SIR) of High rather than Medium as the score indicates. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sec-client-priv-esc-muF8eZdm Security Impact Rating: High CVE: CVE-2026-76462

What to do

Install the fixed versions listed in the official advisory. If you cannot update right away, apply the workarounds or mitigations it describes and limit access to the affected service.

Details

Vendor

Cisco

Product

Cisco Secure Client

CVE

CVE-2026-76462

Affected versions

Cisco Secure Client 4.9: 9 versions, from 4.9.00086 to 4.9.06037
Cisco Secure Client 4.10: 16 versions, from 4.10.00093 to 4.10.08029
Cisco Secure Client 5.0: 9 versions, from 5.0.00238 to 5.0.05040
Cisco Secure Client 5.1: 23 versions, from 5.1.0.136 to 5.1.19.1862 (from the advisory and NVD; check the exact builds in the official advisory)

CVSS score

5.5

Actively exploited

Not known at this time

Source

Cisco PSIRT – original advisory

Published

October 21, 2026

The description and the recommended action are quoted from the public advisory (the action is our generic advice); severity, exploitation status and affected versions are compiled automatically from public sources and may contain errors. The vendor's original advisory prevails: check it before taking action. This information is provided without warranty and does not replace a professional assessment.