CVE-2025-8040

Description

Memory safety bugs present in Firefox ESR 140.0, Thunderbird ESR 140.0, Firefox 140 and Thunderbird 140. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 141, Firefox ESR 140.1, Thunderbird 141, and Thunderbird 140.1.

PUBLISHED Reserved 2025-07-22 | Published 2025-07-22 | Updated 2026-04-13 | Assigner mozilla

Product status

Credits

Andrew McCreight, Ashley Zebrowski

References

bugzilla.mozilla.org/buglist.cgi?bug_id=1975058%2C1975998 (Memory safety bugs fixed in Firefox ESR 140.1, Thunderbird ESR 140.1, Firefox 141 and Thunderbird 141)

www.mozilla.org/security/advisories/mfsa2025-56/

www.mozilla.org/security/advisories/mfsa2025-59/

www.mozilla.org/security/advisories/mfsa2025-61/

www.mozilla.org/security/advisories/mfsa2025-63/

cve.org (CVE-2025-8040)

nvd.nist.gov (CVE-2025-8040)

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