High 7.5Published Jul 8, 2026

CVE-2026-59724Socket.IO enables bidirectional and low-latency communication for every platform.

Updated under an hour ago (2026-10-19 08:30 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for socket engine.io

Exploited in the last 30 days

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 (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-20
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Analyzed
Record last updated: Jul 13, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

socket engine.io socket:engine.io	from 6.5.0 before 6.6.7	NVD

References

https://github.com/socketio/socket.io/commit/1fa1f46cd420ac5b57bb4c04c959b58f3c79158cpatch
https://github.com/socketio/socket.io/releases/tag/engine.io@6.6.7release-notes
https://github.com/socketio/socket.io/security/advisories/GHSA-gr94-w7qr-f4j3patch, vendor-advisory, mitigation

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.