CVE-2020-5941 Explained : Impact and Mitigation

A vulnerability in BIG-IP versions 16.0.0-16.0.0.1 and 15.1.0-15.1.0.5 could lead to a Denial of Service (DoS) attack when using a specific command within an iRule.

Understanding CVE-2020-5941

This CVE involves a potential DoS risk on certain versions of BIG-IP due to a specific command usage.

What is CVE-2020-5941?

This CVE refers to a vulnerability in BIG-IP versions 16.0.0-16.0.0.1 and 15.1.0-15.1.0.5 that triggers a DoS condition when utilizing the RESOLV::lookup command within an iRule.

The Impact of CVE-2020-5941

The vulnerability can cause the Traffic Management Microkernel (TMM) to generate a core file and restart, leading to service disruption.

Technical Details of CVE-2020-5941

This section provides more technical insights into the vulnerability.

Vulnerability Description

When data exceeding the maximum hostname limit is passed to the RESOLV::lookup command, TMM may crash, resulting in a DoS condition.

Affected Systems and Versions

Product: BIG-IP
Versions: 16.0.0-16.0.0.1, 15.1.0-15.1.0.5

Exploitation Mechanism

The issue arises from the improper handling of data exceeding the hostname limit within the RESOLV::lookup command.

Mitigation and Prevention

Protect your systems from this vulnerability by following these steps:

Immediate Steps to Take

Apply the necessary patches provided by the vendor.
Monitor system logs for any unusual activities that might indicate an ongoing attack.

Long-Term Security Practices

Regularly update and patch your BIG-IP systems to prevent known vulnerabilities.
Implement proper input validation mechanisms to prevent data exceeding limits.

Patching and Updates

Ensure timely installation of patches and updates released by the vendor to address this vulnerability.