CVE-2021-34788: Cisco AnyConnect Secure Mobility Client

High severity, CVSS 7.0. EPSS: 0.2% chance of exploitation in the next 30 days.

A vulnerability in the shared library loading mechanism of Cisco AnyConnect Secure Mobility Client for Linux and Mac OS could allow an authenticated, local attacker to perform a shared library hijacking attack on an affected device if the VPN Posture (HostScan) Module is installed on the AnyConnect client. This vulnerability is due to a race condition in the signature verification process for shared library files that are loaded on an affected device. An attacker could exploit this vulnerability by sending a series of crafted interprocess communication (IPC) messages to the AnyConnect process. A successful exploit could allow the attacker to execute arbitrary code on the affected device with root privileges. To exploit this vulnerability, the attacker must have a valid account on the system.

Affected products

• Cisco AnyConnect Secure Mobility Client: before 4.10.03104 (fixed in 4.10.03104)

Published 2021-10-06. Last modified 2026-06-17.