CVE-2026-29004

Name	CVE-2026-29004
Description	BusyBox before commit 42202bf contains a heap buffer overflow vulnerability in the DHCPv6 client (udhcpc6) DNS_SERVERS option handler in networking/udhcp/d6_dhcpc.c that allows network-adjacent attackers to trigger memory corruption by sending a crafted DHCPv6 response with a malformed D6_OPT_DNS_SERVERS option. Attackers can exploit incorrect heap buffer allocation calculations in the option_to_env() function to cause denial of service or achieve arbitrary code execution on embedded systems without heap hardening.
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
busybox (PTS)	bullseye	1:1.30.1-6	vulnerable
	bullseye (security)	1:1.30.1-6+deb11u1	vulnerable
	bookworm	1:1.35.0-4	vulnerable
	trixie	1:1.37.0-6	vulnerable
	forky, sid	1:1.37.0-10.1	vulnerable

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

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

Notes

https://git.busybox.net/busybox/commit/archival?id=42202bfb1e6ac51fa995beda8be4d7b654aeee2a
https://git.busybox.net/busybox/commit/archival?id=d368f3f7836d1c2484c8f839316e5c93e76d4409