CVE-2026-59725

Summary

Socket.IO enables bidirectional and low-latency communication for every platform. From 4.1.0 before 6.6.7, Engine.IO protocol v4 polling transport does not properly close the HTTP response for invalid binary POST requests with Content-Type: application/octet-stream, allowing an unauthenticated attacker to exhaust server-side connections and sockets. This issue is fixed in version 6.6.7.

Affected Software

VendorProductVersion RangeStatus
socketiosocket.io>= 4.1.0, < 6.6.7affected

Weaknesses

  • CWE-404: CWE-404: Improper Resource Shutdown or Release

ADP Enrichment

CISA ADP Vulnrichment

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

References