CVE-2021-22985 : What You Need to Know

This article provides insights into CVE-2021-22985, a vulnerability impacting BIG-IP APM version 16.0.x before 16.0.1.1.

Understanding CVE-2021-22985

CVE-2021-22985 is a Denial of Service (DoS) vulnerability affecting BIG-IP APM, allowing an authenticated VPN user to exploit the system and cause a DoS attack under specific conditions.

What is CVE-2021-22985?

The vulnerability in BIG-IP APM version 16.0.x before 16.0.1.1 enables a malicious VPN user to trigger a DoS attack by causing excessive memory consumption in the Traffic Management Microkernel (TMM) when processing VPN traffic.

The Impact of CVE-2021-22985

A successful exploitation of this vulnerability may lead to a DoS attack against the APM, disrupting its normal operation and affecting the availability of VPN services.

Technical Details of CVE-2021-22985

This section covers the specific technical aspects of the CVE.

Vulnerability Description

Under certain conditions, when VPN traffic is processed with APM, TMM can consume excessive memory, allowing an authenticated VPN user to perform a DoS attack.

Affected Systems and Versions

BIG-IP APM version 16.0.x before 16.0.1.1 is affected by this vulnerability. Other versions are not evaluated for this issue.

Exploitation Mechanism

The vulnerability can be exploited by a malicious, authenticated VPN user who can abuse the memory consumption issue to execute a DoS attack.

Mitigation and Prevention

To mitigate the risks associated with CVE-2021-22985, certain steps need to be taken.

Immediate Steps to Take

Users are advised to upgrade BIG-IP APM to version 16.0.1.1 or apply vendor-supplied patches to address this vulnerability.

Long-Term Security Practices

Implement network segmentation, access controls, and monitoring to enhance the security posture of the APM deployment.

Patching and Updates

Regularly apply software updates and security patches provided by F5 to ensure the ongoing protection of the BIG-IP APM deployment.