CVE-2026-33151

Summary

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.

Affected Software

VendorProductVersion RangeStatus
socketiosocket.io< 3.3.5affected
socketiosocket.io>= 3.4.0, < 3.4.4affected
socketiosocket.io>= 4.0.0, < 4.2.6affected

Weaknesses

  • CWE-20: CWE-20: Improper Input Validation
  • CWE-754: CWE-754: Improper Check for Unusual or Exceptional Conditions

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References