Improper input validation in Socket Socket.io-Parser

CVE-2026-33151

Socket.IO is an open source, real-time, bidirectional, event-based, communication framework. Prior to versions 3.3.5, 3.4.4, and 4.2.6, a specially crafted Socket.IO packet can make the server wait for a large number of binary attachments and buffer them, which can be exploited to make the server run out of memory. This issue has been patched in versions 3.3.5, 3.4.4, and 4.2.6.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.005 (40.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-33151?
CVE-2026-33151 is a high-severity vulnerability in Socket Socket.io-Parser, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2026-03-20.
How severe is CVE-2026-33151?
High severity. CVSS v3 base score is 7.5 out of 10.