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CVE-2026-59724

CVE-2026-59724 · Socket.IO: Engine.IO WebTransport SID DoS

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Socket.IO enables bidirectional and low-latency communication for every platform. From 6.5.0 before 6.6.7, Engine.IO servers with WebTransport enabled can resolve a crafted session ID such as __proto__ through an inherited property of the clients object during WebTransport upgrade handling, causing a TypeError and denial of service. This issue is fixed in version 6.6.7.

CVSS 7.5 · High · EPSS 0.6% · Fix available

Published
Updated

Stack: node

Affected products and versions

  • socket.io

    Versions
    • >= 6.5.0, < 6.6.7: Affected

    No fix published

  • engine.io npm

    Affected ranges
    • SEMVER: ≥ 6.5.0, < 6.6.7

    Update to 6.6.7

Original sources

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