CVE-2026-85197: libsoup3 Use After Free

Vulnerability summary

CVE-2026-85197 is a high (CVSS 7.6) Use After Free vulnerability in libsoup3. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 17.8% of scored vulnerabilities.

Timeline

1. 04-09-2026
   PublishedVulnerability first disclosed.
2. 14-10-2026
   Last modifiedVulnerability information updated.

Description

A flaw was found in libsoup. A malicious HTTP/2 server or a Man-in-the-Middle (MITM) attacker can exploit a heap use-after-free vulnerability in the HTTP/2 client implementation. This occurs when a GNOME application uploads a file using HTTP/2, and the server sends a GOAWAY frame while the file body is being read asynchronously. This can lead to memory corruption, potentially resulting in information disclosure or arbitrary code execution.

• CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.