CVE-2026-57962

Name	CVE-2026-57962
Description	A malicious LDAP server, which a Thunderbird user is configured to query for address-book autocomplete, can stash arbitrarily large amounts of attacker-supplied data into the Thunderbird LDAP client until it crashes due to memory exhaustion. This vulnerability was fixed in Thunderbird 152.0.1 and Thunderbird 140.12.1.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

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)	1:140.12.0esr-1~deb11u1	vulnerable
	bookworm, bookworm (security)	1:140.12.0esr-1~deb12u1	vulnerable
	trixie (security), trixie	1:140.12.0esr-1~deb13u1	vulnerable
	forky, sid	1:140.12.0esr-1	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
thunderbird	source	(unstable)	(unfixed)

Notes

[trixie] - thunderbird <postponed> (Minor issue, wait for next security round)
https://www.mozilla.org/en-US/security/advisories/mfsa2026-64/#CVE-2026-57962