CVE-2026-59725
Socket.IO: Engine.IO Polling Transport Connection Exhaustion
- State
- Published
- Severity
- 7.5 High
- Published
- Jul 8, 2026
- Updated
- Oct 14, 2026
- Reserved
- Jul 6, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.5 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | GitHub_M |
Weaknesses
- CWE-404 Improper Resource Shutdown or Release
Affected Products
| Product | Versions |
|---|---|
engine.iosocketio |
|
References
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