CVE-2025-4948: libsoup2.4 Integer Underflow (Wrap or Wraparound)

Vulnerability summary

CVE-2025-4948 is a high (CVSS 7.5) Integer Underflow (Wrap or Wraparound) vulnerability in libsoup2.4. EPSS estimates a 0.81% chance of exploitation in the next 30 days, higher than 56.2% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

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

Description

A flaw was found in the soup_multipart_new_from_message() function of the libsoup HTTP library, which is commonly used by GNOME and other applications to handle web communications. The issue occurs when the library processes specially crafted multipart messages. Due to improper validation, an internal calculation can go wrong, leading to an integer underflow. This can cause the program to access invalid memory and crash. As a result, any application or server using libsoup could be forced to exit unexpectedly, creating a denial-of-service (DoS) risk.

• CWE-191Integer Underflow (Wrap or Wraparound)The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.