CVE-2026-3099

Name	CVE-2026-3099
Description	A flaw was found in Libsoup. The server-side digest authentication implementation in the SoupAuthDomainDigest class does not properly track issued nonces or enforce the required incrementing nonce-count (nc) attribute. This vulnerability allows a remote attacker to capture a single valid authentication header and replay it repeatedly. Consequently, the attacker can bypass authentication and gain unauthorized access to protected resources, impersonating the legitimate user.
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	1129316

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
libsoup2.4 (PTS)	bullseye	2.72.0-2	vulnerable
	bullseye (security)	2.72.0-2+deb11u3	vulnerable
	bookworm	2.74.3-1+deb12u1	vulnerable
	trixie	2.74.3-10.1	vulnerable
libsoup3 (PTS)	bookworm	3.2.3-0+deb12u2	vulnerable
	trixie	3.6.5-3	vulnerable
	forky, sid	3.6.6-1	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
libsoup2.4	source	(unstable)	(unfixed)
libsoup3	source	(unstable)	(unfixed)			1129316

Notes

[trixie] - libsoup3 <no-dsa> (Minor issue)
[bookworm] - libsoup3 <no-dsa> (Minor issue)
[trixie] - libsoup2.4 <no-dsa> (Minor issue)
[bookworm] - libsoup2.4 <no-dsa> (Minor issue)
https://gitlab.gnome.org/GNOME/libsoup/-/issues/495