Use-after-free during concurrent delazification
Vulnerability Description
A race during concurrent delazification could have led to a use-after-free. This vulnerability was fixed in Firefox 135, Firefox ESR 115.20, Firefox ESR 128.7, Thunderbird 128.7, and Thunderbird 135.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:
- Nils Bars
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1939710
- https://www.mozilla.org/security/advisories/mfsa2025-07/
- https://www.mozilla.org/security/advisories/mfsa2025-08/
- https://www.mozilla.org/security/advisories/mfsa2025-09/
- https://www.mozilla.org/security/advisories/mfsa2025-10/
- https://www.mozilla.org/security/advisories/mfsa2025-11/
More from Mozilla
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Mozilla
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Timeline
CVSS Vectors
Weaknesses (CWE)
No CWE data available
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.