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)
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.006 (48.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 48th percentile — 48.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.006 · change: +0.001
Affected products
- Socket Socket.io-Parser
- Socketio Socket.io — versions < 3.3.5, >= 3.4.0, < 3.4.4, >= 4.0.0, < 4.2.6
Weakness classification (CWE)
References
- github.com/socketio/socket.io/security/advisories/GHSA-677m-j7p3-52f9 (Patch, Vendor Advisory)
- github.com/socketio/socket.io/commit/719f9ebab0772ffb882bd614b387e585c1aa75d4 (Patch)
- github.com/socketio/socket.io/commit/9d39f1f080510f036782f2177fac701cc041faaf (Patch)
- github.com/socketio/socket.io/commit/b25738c416c4e32fbff62ee182afa8f6d0dacf78 (Patch)
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.