cvedb.io
CVE-2026-5067
CRITICAL · CVSS 9.8
EPSS exploitation probability: 0%
Published 2026-06-09T06:16:53.920 · Last modified 2026-06-17T10:58:23.143

Summary

A remote, unauthenticated attacker can trigger memory corruption in Zephyr's HTTP server WebSocket upgrade path by sending a crafted Sec-WebSocket-Key header. The HTTP/1 header parser copies the header into a fixed-size buffer using a bounded copy that does not guarantee NUL termination when the input length reaches the buffer size. During upgrade handling the buffer is copied to a local stack buffer and passed to strlen(); if no NUL exists in-bounds, strlen() reads beyond the stack buffer and subsequent concatenation with the WebSocket magic string can write out of bounds. This leads to out-of-bounds read and write on stack memory, resulting in crash (denial of service) and potentially code execution. The path is reachable when CONFIG_HTTP_SERVER_WEBSOCKET is enabled.

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.