VULNERABILITY INTELLIGENCE

CVE-2026-59724

CVSS score7.5 HIGH
EPSS probability0.61%
CISA KEVNot currently listed
Published2026-07-08
Last modified2026-10-25
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

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.

Weakness classification

  • CWE-20: Improper Input Validation

Primary references