CVE-2026-50161

Name of the Vulnerable Software and Affected Versions libre versions prior to 4.8.1

Description The websock decode() function in src/websock/websock.c contains an integer overflow during the validation of a masked WebSocket frame utilizing 64-bit extended length encoding. When the hdr->len variable is close to UINT64 MAX, the expression 4 + hdr->len can wrap, allowing the mbuf get left() bounds check to pass. This leads to a heap buffer overflow during the subsequent XOR unmasking loop. Applications implementing a WebSocket server via websock accept() or websock accept proto() are affected, potentially resulting in attacker-controlled heap corruption or denial of service following the HTTP WebSocket upgrade handshake.

Recommendations Update to version 4.8.1.