CVE-2023-5174: mozilla firefox Use After Free

Vulnerability summary

CVE-2023-5174 is a critical (CVSS 9.8) Use After Free vulnerability in mozilla firefox. EPSS estimates a 1.20% chance of exploitation in the next 30 days, higher than 67.9% of scored vulnerabilities.

Timeline

1. 27-09-2023
   PublishedVulnerability first disclosed.
2. 05-05-2025
   Last modifiedVulnerability information updated.

Description

If Windows failed to duplicate a handle during process creation, the sandbox code may have inadvertently freed a pointer twice, resulting in a use-after-free and a potentially exploitable crash. *This bug only affects Firefox on Windows when run in non-standard configurations (such as using `runas`). Other operating systems are unaffected.* This vulnerability affects Firefox < 118, Firefox ESR < 115.3, and Thunderbird < 115.3.

• 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 Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.