CVE-2025-4476: A denial-of-service vulnerability has been identified in the libsoup HTTP client library. This flaw can be triggered when a libsoup client receives a 401…

medium4.3CVSS 3.1

AVNACLPRNUIRSUCNINAL

A denial-of-service vulnerability has been identified in the libsoup HTTP client library. This flaw can be triggered when a libsoup client receives a 401 (Unauthorized) HTTP response containing a specifically crafted domain parameter within the WWW-Authenticate header. Processing this malformed header can lead to a crash of the client application using libsoup. An attacker could exploit this by setting up a malicious HTTP server. If a user's application using the vulnerable libsoup library connects to this malicious server, it could result in a denial-of-service. Successful exploitation requires tricking a user's client application into connecting to the attacker's malicious server.

Affected

5 ranges

Vendor	Product	Version range	Fixed in
debian	libsoup2.4	< libsoup2.4 2.72.0-2+deb11u3 (bullseye)	libsoup2.4 2.72.0-2+deb11u3 (bullseye)
debian	libsoup3	< libsoup2.4 2.72.0-2+deb11u3 (bullseye)	libsoup2.4 2.72.0-2+deb11u3 (bullseye)
msrc	azl3_libsoup_3.4.4-7_on_azure_linux_3.0	—	—
msrc	cbl2_libsoup_3.0.4-7_on_cbl_mariner_2.0	—	—
msrc	cm2_libsoup_3.0.4-7_on_cbl_mariner_2.0	—	—

CVSS provenance

nvdv3.14.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

osv7.5HIGH