CVE-2026-84965

Name	CVE-2026-84965
Description	An integer wraparound in an allocation size calculation in the BSON library's JSON parsing code can cause a buffer to be released while a following copy operation still writes through the stale pointer. On builds where sizes are 32 bits, an unauthenticated party able to supply a sufficiently large JSON input to an application that links the library may cause that application to terminate unexpectedly, resulting in denial of service.
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
mongo-c-driver (PTS)	bookworm	1.23.1-1+deb12u3	vulnerable
	trixie	1.30.4-1+deb13u2	vulnerable
	forky	2.5.1-1	vulnerable
	sid	2.5.2-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
mongo-c-driver	source	(unstable)	2.5.2-1

Notes

[trixie] - mongo-c-driver <no-dsa> (Minor issue)
https://jira.mongodb.org/browse/CDRIVER-6405
Fixed by: https://github.com/mongodb/mongo-c-driver/commit/8a4c4416a171b66a3eb0b136f844c62ca9e36025 (2.5.2)
Fixed by: https://github.com/mongodb/mongo-c-driver/commit/aba72444f8e8950b8a57636b1ad72a5a853f8264 (1.30.9)