CVE-2026-5124

Name	CVE-2026-5124
Description	A security vulnerability has been detected in osrg GoBGP up to 4.3.0. Affected is the function BGPHeader.DecodeFromBytes of the file pkg/packet/bgp/bgp.go of the component BGP Header Handler. The manipulation leads to improper access controls. Remote exploitation of the attack is possible. The attack is considered to have high complexity. The exploitability is told to be difficult. The identifier of the patch is f0f24a2a901cbf159260698211ab15c583ced131. To fix this issue, it is recommended to deploy a patch.
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)
Debian Bugs	1132653

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
gobgp (PTS)	bullseye	2.25.0-2	vulnerable
	bookworm	3.10.0-1	vulnerable
	trixie	3.36.0-2	vulnerable
	sid, forky	4.5.0-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
gobgp	source	(unstable)	4.4.0-1	unimportant		1132653

Notes

https://github.com/osrg/gobgp/pull/3340
Fixed by: https://github.com/osrg/gobgp/commit/f0f24a2a901cbf159260698211ab15c583ced131 (v4.4.0)
Not a security issue per upstream assessment:
https://github.com/osrg/gobgp/issues/3362#issuecomment-4248281007