CVE-2025-14523

Name	CVE-2025-14523
Description	A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost confusion where a proxy routes a request to one backend but the backend interprets it as destined for another host. This discrepancy enables request-smuggling style attacks, cache poisoning, or bypassing host-based access controls when an attacker supplies duplicate Host headers.
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
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
	sid	2.74.3-11	vulnerable
libsoup3 (PTS)	bookworm	3.2.3-0+deb12u2	vulnerable
	trixie	3.6.5-3	vulnerable
	forky, sid	3.6.5-5	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)

https://gitlab.gnome.org/GNOME/libsoup/-/issues/472