CVE-2025-4035

Libsoup: cookie domain validation bypass via uppercase characters in libsoup

State: Published
Severity: 4.3 Medium
Published: Apr 29, 2025
Updated: Jun 30, 2026
Reserved: Apr 28, 2025

Description

A flaw was found in libsoup. When handling cookies, libsoup clients mistakenly allow cookies to be set for public suffix domains if the domain contains at least two components and includes an uppercase character. This bypasses public suffix protections and could allow a malicious website to set cookies for domains it does not own, potentially leading to integrity issues such as session fixation.

Scores

CVSS	Score	Vector	Source
3.1	4.3 Medium	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N	redhat

Weaknesses

CWE-178 Improper Handling of Case Sensitivity

Affected Products

Product	Versions
Red Hat Enterprise Linux 10Red Hat	0:3.6.5-3.el10_0.6 and laterNot affected
Red Hat Enterprise Linux 6Red Hat
Red Hat Enterprise Linux 7Red Hat
Red Hat Enterprise Linux 8Red Hat
Red Hat Enterprise Linux 9Red Hat

References

RHSA-2025:8128vendor-advisory
https://access.redhat.com/security/cve/CVE-2025-4035vdb-entry
RHBZ#2362651issue-tracking
https://gitlab.gnome.org/GNOME/libsoup/-/issues/443
https://gitlab.gnome.org/GNOME/libsoup/-/work_items/443exploit

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