CVE-2026-12478

Name of the Vulnerable Software and Affected Versions libsoup versions prior to 3.6.6

Description An integer overflow guard was incorrectly placed within a conditional block, leaving unmasked server-to-client frames unprotected. A malicious WebSocket server can send a crafted unmasked frame with a payload length near UINT64 MAX to trigger an out-of-bounds (OOB) read in a client when max incoming payload size is set to 0. An OOB read occurs when a program reads data past the end of the intended buffer.

Recommendations Update to version 3.6.6.