CVE-2026-59725 (GCVE-0-2026-59725)

Vulnerability from cvelistv5 – Published: 2026-07-08 15:37 – Updated: 2026-10-14 18:46
VLAI
Title
Socket.IO: Engine.IO Polling Transport Connection Exhaustion
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-08 16:50 UTC
CWE
  • CWE-404 - Improper Resource Shutdown or Release
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8035 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
socketio engine.io Affected: >= 4.1.0, < 6.6.7
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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