CVE-2026-24869 Mozilla CVE debrief

Who should care

This vulnerability affects users of Mozilla Firefox. Specifically, any user of Firefox prior to version 147.0.2 is potentially vulnerable to this issue. Organizations and individuals who use Firefox for browsing the internet should prioritize updating to the latest version to mitigate the risk associated with this vulnerability.

Technical summary

The CVE-2026-24869 vulnerability is a use-after-free issue in the Layout: Scrolling and Overflow component of Firefox. This type of vulnerability occurs when a program attempts to use memory after it has been freed or deleted. This can lead to unpredictable behavior, crashes, or, in the case of vulnerabilities like this, potentially allow an attacker to execute arbitrary code. The vulnerability was assigned a CVSS score of 8.8, indicating high severity. The vulnerability was publicly disclosed on January 27, 2026.

Defensive priority

High priority should be given to updating Firefox to version 147.0.2 or later to mitigate this vulnerability. Given the high CVSS score of 8.8, indicating high severity, defenders should treat this as a critical update.

Recommended defensive actions

• Update Firefox to version 147.0.2 or later immediately.
• Ensure all Firefox installations within the organization are updated.
• Monitor Firefox installations for compliance with the updated version.
• Consider implementing a vulnerability management process to ensure timely updates of critical software.
• Review and update incident response plans to include procedures for rapid deployment of patches for high-severity vulnerabilities.

Evidence notes

The CVE-2026-24869 vulnerability was publicly disclosed on January 27, 2026, with a CVSS score of 8.8. It affects Firefox versions prior to 147.0.2. The vulnerability is a use-after-free issue in the Layout: Scrolling and Overflow component. The Common Weakness Enumeration (CWE) for this vulnerability is CWE-416. The vulnerability was fixed in Firefox version 147.0.2.

Official resources