CVE-2018-5537 : Vulnerability Insights and Analysis

A vulnerability in F5 BIG-IP versions 11.2.1 to 13.1.0.5 could allow a remote attacker to disrupt services by exploiting specially crafted HTML content.

Understanding CVE-2018-5537

What is CVE-2018-5537?

If a TMM virtual server on F5 BIG-IP versions 13.0.0 to 13.1.0.5, 12.1.0 to 12.1.3.5, 11.6.0 to 11.6.3.1, or 11.2.1 to 11.5.6 is configured with a HTML or Rewrite profile, a remote attacker could potentially disrupt services by causing the TMM to restart during the handling of specific HTML content.

The Impact of CVE-2018-5537

This vulnerability could lead to a Denial of Service (DoS) condition, affecting the availability of services on the affected F5 BIG-IP devices.

Technical Details of CVE-2018-5537

Vulnerability Description

The vulnerability allows a remote attacker to disrupt services on F5 BIG-IP versions 13.0.0-13.1.0.5, 12.1.0-12.1.3.5, 11.6.0-11.6.3.1, or 11.2.1-11.5.6 if the TMM virtual server is configured with a HTML or a Rewrite profile.

Affected Systems and Versions

Product: BIG-IP (LTM, AAM, AFM, APM, ASM, Edge Gateway, GTM, PEM, WebAccelerator, WebSafe)
Vendor: F5 Networks, Inc.
Versions: 13.0.0-13.1.0.5, 12.1.0-12.1.3.5, 11.6.0-11.6.3.1, 11.2.1-11.5.6

Exploitation Mechanism

The disruption occurs when the TMM restarts while processing specially prepared HTML content from the backend, potentially triggered by a remote attacker.

Mitigation and Prevention

Immediate Steps to Take

Apply the necessary patches provided by F5 Networks, Inc.
Restrict network access to the affected systems.
Monitor for any unusual network activity.

Long-Term Security Practices

Regularly update and patch all software and firmware.
Implement network segmentation to limit the impact of potential attacks.

Patching and Updates

Ensure that all F5 BIG-IP devices are updated with the latest patches and firmware releases.