CVE-2026-59725

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Source
https://cve.org/CVERecord?id=CVE-2026-59725
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-59725.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-59725
Aliases
  • GHSA-r635-g3xr-vw7x
Downstream
Published
2026-07-08T15:37:52.293Z
Modified
2026-07-16T03:48:44.444371860Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
Socket.IO: Engine.IO Polling Transport Connection Exhaustion
Details

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.

Database specific 
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59725.json",
    "cwe_ids": [
        "CWE-404"
    ],
    "cna_assigner": "GitHub_M"
}
References

Affected packages

Git / github.com/socketio/socket.io

Affected ranges

Type
GIT
Repo
https://github.com/socketio/socket.io
Events
Introduced
fb6b0efec9fcc154dc9131189d78fcfa0a6c7f46
Fixed
439a8f669c6788b512dd76011c4476830d67515b
Fixed
fc11285e14964c2132d122164bf130c355f60671
Database specific 
{
    "cpe": "cpe:2.3:a:socket:engine.io:*:*:*:*:*:node.js:*:*",
    "source": [
        "CPE_RANGE",
        "REFERENCES"
    ],
    "extracted_events": [
        {
            "introduced": "4.1.0"
        },
        {
            "fixed": "6.6.7"
        }
    ]
}

Affected versions

4.*
4.1.0
4.1.1
4.1.2
4.1.3
4.2.0
4.3.0
4.3.1
4.3.2
4.4.0
4.4.1
4.5.0
4.5.1
4.5.2
4.5.3
4.5.4
4.6.0
4.6.0-alpha1
4.6.1
4.6.2
4.7.0
4.7.1
4.7.2
4.7.3
4.7.4
4.7.5
@socket.*
@socket.io/cluster-adapter@0.3.0
@socket.io/cluster-engine@0.1.0
@socket.io/postgres-emitter@0.1.1
@socket.io/redis-streams-emitter@0.1.0
@socket.io/redis-streams-emitter@0.1.1
engine.*
engine.io-client@6.6.1
engine.io-client@6.6.2
engine.io-client@6.6.3
engine.io-client@6.6.4
engine.io-parser@5.2.3
engine.io@6.6.1
engine.io@6.6.2
engine.io@6.6.3
engine.io@6.6.4
engine.io@6.6.5
engine.io@6.6.6
socket.*
socket.io-adapter@2.5.6
socket.io-client@4.8.0
socket.io-client@4.8.1
socket.io-client@4.8.2
socket.io-client@4.8.3
socket.io-parser@4.2.5
socket.io@4.7.5
socket.io@4.8.0
socket.io@4.8.1
socket.io@4.8.2
socket.io@4.8.3

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-59725.json"