CVE-2026-106434

Name	CVE-2026-106434
Description	The explicit decryption component of MongoDB libmongocrypt can return an unrecognized encrypted payload unchanged instead of returning a decryption error. An actor who can modify stored encrypted fields, such as a database writer, server, or network intermediary, can cause an affected application to process the supplied bytes as decrypted plaintext.
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
libmongocrypt (PTS)	bookworm	1.7.2-1	vulnerable
	trixie	1.13.2-1+deb13u1	vulnerable
	forky	1.20.4-1	vulnerable
	sid	1.20.5-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
libmongocrypt	source	(unstable)	1.20.5-1

Notes

https://jira.mongodb.org/browse/MONGOCRYPT-966
Fixed by: https://github.com/mongodb/libmongocrypt/commit/5e68bbf5825b59978e21c595c1af6d39a5e00e94 (1.20.5)
Fixed by: https://github.com/mongodb/libmongocrypt/commit/e9d07e8a7d593dde93681943b7070634aebd1980 (1.20.5)