CVE-2026-16367: mozilla firefox

Vulnerability summary

CVE-2026-16367 is a critical (CVSS 10.0) vulnerability in mozilla firefox. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 30.2% of scored vulnerabilities.

Timeline

1. 21-07-2026
   PublishedVulnerability first disclosed.
2. 22-07-2026
   Last modifiedVulnerability information updated.

Description

Sandbox escape due to invalid pointer in the Disability Access APIs component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.

• CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferThe product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
• 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 Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.