// For flags

CVE-2025-4035

Libsoup: cookie domain validation bypass via uppercase characters in libsoup

Severity Score

4.3
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

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.

An update for libsoup3 is now available for Red Hat Enterprise Linux 10. Issues addressed include bypass and denial of service vulnerabilities.

*Credits: Red Hat would like to thank Jan Różański for reporting this issue.
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
Partial
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2025-04-28 CVE Reserved
  • 2025-04-29 CVE Published
  • 2025-05-26 CVE Updated
  • 2025-07-06 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-178: Improper Handling of Case Sensitivity
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Red Hat
Search vendor "Red Hat"
 Enterprise Linux
Search vendor "Red Hat" for product "Enterprise Linux"
*-
Affected
Redhat
Search vendor "Redhat"
 Enterprise Linux
Search vendor "Redhat" for product "Enterprise Linux"
*-
Affected