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CVE-2025-6424

Published: Jun 24, 2025

Modified: Apr 13, 2026

PUBLISHED

Description

A use-after-free in FontFaceSet resulted in a potentially exploitable crash. This vulnerability was fixed in Firefox 140, Firefox ESR 115.25, Firefox ESR 128.12, Thunderbird 140, and Thunderbird 128.12.

Vendor	Product	Versions
Mozilla	Firefox	unaffected `115.25 - <= 115.` unaffected `128.12 - <= 128.` unaffected `140 - <= *`
Mozilla	Thunderbird	unaffected `128.12 - <= 128.` unaffected `140 - <= `

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1966423

https://www.mozilla.org/security/advisories/mfsa2025-51/

https://www.mozilla.org/security/advisories/mfsa2025-52/

https://www.mozilla.org/security/advisories/mfsa2025-53/

https://www.mozilla.org/security/advisories/mfsa2025-54/

https://www.mozilla.org/security/advisories/mfsa2025-55/

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