CVE-2022-26485: Mozilla Firefox Use-After-Free Vulnerability

Vulnerability summary

CVE-2022-26485 is a high (CVSS 8.8) Use After Free vulnerability in Mozilla Firefox. It is known to be exploited: CISA lists it, first on 07-03-2022. EPSS estimates a 14.26% chance of exploitation in the next 30 days, higher than 96.5% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 07-03-2022
   Added to CISA KEVMozilla Firefox Use-After-Free Vulnerability
2. 21-03-2022
   CISA remediation dueApply updates per vendor instructions.
3. 22-12-2022
   PublishedVulnerability first disclosed.
4. 21-10-2025
   Last modifiedVulnerability information updated.

Description

Removing an XSLT parameter during processing could have lead to an exploitable use-after-free. We have had reports of attacks in the wild abusing this flaw. This vulnerability affects Firefox < 97.0.2, Firefox ESR < 91.6.1, Firefox for Android < 97.3.0, Thunderbird < 91.6.2, and Focus < 97.3.0.

• CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.