CVE-2025-0247

CRITICAL 9.8CVE-2025-0247 · Published 07/01/2025 · updated 05/10/2026

Package	Affected versions	Patched versions
firefox mozilla	`< 134.0`	`134.0`
thunderbird mozilla	`< 134.0`	`134.0`

Description

Memory safety bugs present in Firefox 133 and Thunderbird 133. 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 134 and Thunderbird 134.

References

bugzilla.mozilla.org/buglist.cgi · Broken Link
mozilla.org/security/advisories/mfsa2025-01 · Vendor Advisory
mozilla.org/security/advisories/mfsa2025-04 · Vendor Advisory

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