CVE-2026-33151

HIGH EPSS 39.8%
Published Mar 20, 20263mo ago · Modified Jun 17, 20262w ago
8.7 CVSS 4.0
High
Find Similar
Published Mar 20, 2026 3mo ago
Last Modified Jun 17, 2026 2w ago

Description

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.

CVSS Details

Base Score
8.7
Exploitability
Impact
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
39.8% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 2

CWE-20 Improper Input Validation Validation
CWE-754

Affected Products 3

VendorProductVersionRange
socketsocket.io-parser* <3.3.5
socketsocket.io-parser*≥3.4.0  –  <3.4.4
socketsocket.io-parser*≥4.0.0  –  <4.2.6

References 4

  • github.com https://github.com/socketio/socket.io/commit/719f9ebab0772ffb882bd614b387e585c1aa75d4
    Patch
  • github.com https://github.com/socketio/socket.io/commit/9d39f1f080510f036782f2177fac701cc041faaf
    Patch
  • github.com https://github.com/socketio/socket.io/commit/b25738c416c4e32fbff62ee182afa8f6d0dacf78
    Patch
  • github.com https://github.com/socketio/socket.io/security/advisories/GHSA-677m-j7p3-52f9
    PatchVendor Advisory

Remediation

  • github.com https://github.com/socketio/socket.io/commit/719f9ebab0772ffb882bd614b387e585c1aa75d4
    Patch
  • github.com https://github.com/socketio/socket.io/commit/9d39f1f080510f036782f2177fac701cc041faaf
    Patch
  • github.com https://github.com/socketio/socket.io/commit/b25738c416c4e32fbff62ee182afa8f6d0dacf78
    Patch
  • github.com https://github.com/socketio/socket.io/security/advisories/GHSA-677m-j7p3-52f9
    PatchVendor Advisory