CVE-2021-1366 Explained : Impact and Mitigation

A vulnerability in the interprocess communication (IPC) channel of Cisco AnyConnect Secure Mobility Client for Windows could allow an authenticated, local attacker to perform a DLL hijacking attack on an affected device, potentially leading to the execution of arbitrary code with SYSTEM privileges.

Understanding CVE-2021-1366

This CVE-2021-1366 pertains to a security vulnerability in Cisco AnyConnect Secure Mobility Client for Windows that could be exploited by an authenticated, local attacker.

What is CVE-2021-1366?

The vulnerability allows an attacker to perform a DLL hijacking attack on an affected device and execute arbitrary code with SYSTEM privileges by exploiting insufficient validation of resources loaded by the application at runtime.

The Impact of CVE-2021-1366

Successful exploitation could lead to the unauthorized execution of code with elevated privileges on the affected Windows system.

Technical Details of CVE-2021-1366

This section covers the specific technical details of the vulnerability.

Vulnerability Description

The vulnerability arises from the IPC channel of Cisco AnyConnect Secure Mobility Client for Windows lacking proper validation of loaded resources, enabling an attacker to send a crafted IPC message and execute arbitrary code on the target system.

Affected Systems and Versions

The vulnerability affects Cisco AnyConnect Secure Mobility Client for Windows when the VPN Posture (HostScan) Module is installed.

Exploitation Mechanism

By sending a specially crafted IPC message to the AnyConnect process, an authenticated, local attacker can trigger the vulnerability to execute malicious code with SYSTEM privileges.

Mitigation and Prevention

To address CVE-2021-1366, it is crucial to implement the following security measures.

Immediate Steps to Take

Users are advised to apply security updates provided by Cisco to mitigate the risk of exploitation. Additionally, monitor network traffic for any signs of malicious activity that may indicate an ongoing attack.

Long-Term Security Practices

Regularly update the affected software and follow security best practices to reduce the overall attack surface.

Patching and Updates

Stay informed about security advisories from Cisco and promptly apply patches to secure the affected systems.