CVE-2026-12309

Vulnerability

A memory safety bug was present in Firefox and Firefox ESR, leading to potential exploitation. The vulnerability was fixed in Firefox 152 and Firefox ESR 140.12 [1][2]. The exact component affected is not specified in the available references, but the bug is classified as a memory safety issue.

Exploitation

The exploitation details are not disclosed in the available references. Memory safety bugs typically require an attacker to craft specific inputs or trigger certain conditions to corrupt memory. No authentication or user interaction details are provided in the referenced advisories [1][2].

Impact

The impact is rated as high by Mozilla [1][2]. Successful exploitation could lead to memory corruption, potentially resulting in arbitrary code execution or other consequences. The specific CIA outcome is not detailed beyond the generic high severity classification.

Mitigation

The vulnerability is fixed in Firefox 152 and Firefox ESR 140.12, both released on June 16, 2026 [1][2]. Users should update to these versions or later. No workarounds are mentioned, and the product is not listed as end-of-life. The CVE does not appear on the CISA Known Exploited Vulnerabilities (KEV) catalog as of the publication date.