CVE-2025-3932

Name	CVE-2025-3932
Description	It was possible to craft an email that showed a tracking link as an attachment. If the user attempted to open the attachment, Thunderbird automatically accessed the link. The configuration to block remote content did not prevent that. Thunderbird has been fixed to no longer allow access to web pages listed in the X-Mozilla-External-Attachment-URL header of an email. This vulnerability affects Thunderbird < 128.10.1 and Thunderbird < 138.0.1.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-4167-1, DSA-5921-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
thunderbird (PTS)	bullseye	1:115.12.0-1~deb11u1	vulnerable
	bullseye (security)	1:128.11.0esr-1~deb11u1	fixed
	bookworm	1:128.10.0esr-1~deb12u1	vulnerable
	bookworm (security)	1:128.11.0esr-1~deb12u1	fixed
	sid, trixie	1:128.11.0esr-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Origin
thunderbird	source	bullseye	1:128.10.1esr-1~deb11u1	DLA-4167-1
thunderbird	source	bookworm	1:128.10.1esr-1~deb12u1	DSA-5921-1
thunderbird	source	(unstable)	1:128.10.1esr-1

https://www.mozilla.org/en-US/security/advisories/mfsa2025-34/#CVE-2025-3932