CVE-2025-4035 (CVSS 4.3)

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.

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CVSS v3.1 Score

4.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Weakness Type (CWE)

CWE-178 CWE-178

References

Other References

https://access.redhat.com/errata/RHSA-2025:8128 https://access.redhat.com/security/cve/CVE-2025-4035 https://bugzilla.redhat.com/show_bug.cgi?id=2362651

Frequently Asked Questions

What is CVE-2025-4035? +

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. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2025-4035? +

CVE-2025-4035 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2025-4035? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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