Description
A web page could trick a user into setting that site as the default handler for a custom URL protocol. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Mozilla Firefox
128.8 to ≤ 128.*unaffected136 to ≤ *unaffected
Mozilla Thunderbird
128.8 to ≤ 128.*unaffected136 to ≤ *unaffected
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1866661 ↗
- https://www.mozilla.org/security/advisories/mfsa2025-14/ ↗
- https://www.mozilla.org/security/advisories/mfsa2025-16/ ↗
- https://www.mozilla.org/security/advisories/mfsa2025-17/ ↗
- https://www.mozilla.org/security/advisories/mfsa2025-18/ ↗
- https://lists.debian.org/debian-lts-announce/2025/03/msg00006.html ↗