CVE-2025-4945: libsoup3 Integer Overflow or Wraparound

Vulnerability summary

CVE-2025-4945 is a low (CVSS 3.7) Integer Overflow or Wraparound vulnerability in libsoup3. EPSS estimates a 0.70% chance of exploitation in the next 30 days, higher than 52.5% of scored vulnerabilities.

Timeline

1. 19-05-2025
   PublishedVulnerability first disclosed.
2. 30-06-2026
   Last modifiedVulnerability information updated.

Description

A flaw was found in the cookie parsing logic of the libsoup HTTP library, used in GNOME applications and other software. The vulnerability arises when processing the expiration date of cookies, where a specially crafted value can trigger an integer overflow. This may result in undefined behavior, allowing an attacker to bypass cookie expiration logic, causing persistent or unintended cookie behavior. The issue stems from improper validation of large integer inputs during date arithmetic operations within the cookie parsing routines.

• CWE-190Integer Overflow or WraparoundThe product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.