CVE-2024-38355: Socket Socket.io

High severity, CVSS 7.3. EPSS: 0.8% chance of exploitation in the next 30 days.

Socket.IO is an open source, real-time, bidirectional, event-based, communication framework. A specially crafted Socket.IO packet can trigger an uncaught exception on the Socket.IO server, thus killing the Node.js process. This issue is fixed by commit `15af22fc22` which has been included in `socket.io@4.6.2` (released in May 2023). The fix was backported in the 2.x branch as well with commit `d30630ba10`. Users are advised to upgrade. Users unable to upgrade may attach a listener for the "error" event to catch these errors.

Affected products

• Socket Socket.io: before 2.5.1 (fixed in 2.5.1); from 3.0.0, before 4.6.2 (fixed in 4.6.2)
• Socketio Socket.io: before 2.5.1 (fixed in 2.5.1); from 3.0.0, before 4.6.2 (fixed in 4.6.2)

Published 2024-06-19. Last modified 2026-06-17.