libre is a generic library for real-time communications with asynchronous input and output support. Prior to 4.8.1, the websock_decode() function in src/websock/websock.c contains an integer overflow when validating a masked WebSocket frame that uses the 64-bit extended length encoding. The expression 4 + hdr->len can wrap when hdr->len is close to UINT64_MAX, causing the mbuf_get_left() bounds check to pass. The subsequent XOR unmasking loop then writes beyond the heap buffer. Applications using websock_accept() or websock_accept_proto() to implement a WebSocket server are affected, and exploitation can cause attacker-controlled heap corruption or denial of service after the HTTP WebSocket upgrade handshake. This issue is fixed in version 4.8.1.
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History
Tue, 18 Aug 2026 18:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | libre is a generic library for real-time communications with asynchronous input and output support. Prior to 4.8.1, the websock_decode() function in src/websock/websock.c contains an integer overflow when validating a masked WebSocket frame that uses the 64-bit extended length encoding. The expression 4 + hdr->len can wrap when hdr->len is close to UINT64_MAX, causing the mbuf_get_left() bounds check to pass. The subsequent XOR unmasking loop then writes beyond the heap buffer. Applications using websock_accept() or websock_accept_proto() to implement a WebSocket server are affected, and exploitation can cause attacker-controlled heap corruption or denial of service after the HTTP WebSocket upgrade handshake. This issue is fixed in version 4.8.1. | |
| Title | libre: Integer overflow in websock_decode() masked frame length check leads to heap buffer overflow | |
| Weaknesses | CWE-190 CWE-787 |
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cvssV4_0
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-08-18T17:53:01.696Z
Reserved: 2026-06-03T20:54:20.432Z
Link: CVE-2026-50161
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Status : Received
Published: 2026-08-18T18:17:53.380
Modified: 2026-08-18T18:17:53.380
Link: CVE-2026-50161
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OpenCVE Enrichment
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