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.
Details
| Severity | Base Score | CVE |
|---|---|---|
| MEDIUM | 4.3 | CVE-2025-4035 |
Exploitation
To exploit this vulnerability, an attacker could create a malicious website that sets cookies for a public suffix domain by manipulating the domain structure to include uppercase characters. This could lead to session fixation attacks, where the attacker can hijack user sessions.
Affected Products
- libsoup: A library used for HTTP client and server communication, vulnerable to cookie handling issues.
Mitigation
To mitigate this vulnerability, it is recommended to update libsoup to the latest version where this issue has been addressed. Additionally, implementing strict cookie policies and validating domain structures can help prevent similar vulnerabilities.