CVE-2025-11712

Details

A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served without a content-type. This could have contributed to an XSS on a site that unsafely serves files without a content-type header. This vulnerability affects Firefox < 144, Firefox ESR < 140.4, Thunderbird < 144, and Thunderbird < 140.4.

Affected Packages

Firefox

Ubuntu 14.04 LTSUbuntu 16.04 LTSUbuntu 18.04 LTSUbuntu 20.04 LTSUbuntu 22.04 LTS

Fixed in:

144

Mozilla Firefox

Windows 10 (1507)Windows 10 (1607) / Server 2016Windows 10 (1809) / Server 2019Windows 10 (1903)Windows 10 (1909)

Fixed in:

144

Mozilla Firefox ESR

Windows 10 (1507)Windows 10 (1607) / Server 2016Windows 10 (1809) / Server 2019Windows 10 (1903)Windows 10 (1909)

Fixed in:

140.4

Firefox ESR

macOS 14macOS 15macOS 26

Fixed in:

140.4

References

WEBhttps://bugzilla.mozilla.org/show_bug.cgi?id=1979536 WEBhttps://lists.debian.org/debian-lts-announce/2025/10/msg00015.html WEBhttps://lists.debian.org/debian-lts-announce/2025/10/msg00031.html ADVISORYhttps://www.cve.org/CVERecord?id=CVE-2025-11712 WEBhttps://www.mozilla.org/security/advisories/mfsa2025-81/WEBhttps://www.mozilla.org/security/advisories/mfsa2025-83/WEBhttps://www.mozilla.org/security/advisories/mfsa2025-84/WEBhttps://www.mozilla.org/security/advisories/mfsa2025-85/

CVE-2025-11712

Details

Affected Packages

References

CVSS Analysis

Ecosystems(28)

Timeline