{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-102599", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-09-29T14:18:02.920Z", "datePublished": "2026-10-13T19:05:10.870Z", "dateUpdated": "2026-10-13T19:05:10.870Z"}, "containers": {"cna": {"title": "Socket.IO: Engine.IO Protocol Revision Mismatch DoS", "problemTypes": [{"descriptions": [{"cweId": "CWE-248", "lang": "en", "description": "CWE-248: Uncaught Exception", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}}], "references": [{"name": "https://github.com/socketio/socket.io/security/advisories/GHSA-2gc4-cqfq-p2gv", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/socketio/socket.io/security/advisories/GHSA-2gc4-cqfq-p2gv"}, {"name": "https://github.com/socketio/socket.io/commit/86db1fc3db2cd315a065d64c4e48918ccf9b4729", "tags": ["x_refsource_MISC"], "url": "https://github.com/socketio/socket.io/commit/86db1fc3db2cd315a065d64c4e48918ccf9b4729"}, {"name": "https://github.com/socketio/socket.io/releases/tag/engine.io@6.6.10", "tags": ["x_refsource_MISC"], "url": "https://github.com/socketio/socket.io/releases/tag/engine.io@6.6.10"}], "affected": [{"vendor": "socketio", "product": "socket.io", "versions": [{"version": ">= 6.6.0, < 6.6.10", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-10-13T19:05:10.870Z"}, "descriptions": [{"lang": "en", "value": "Socket.IO enables bidirectional and low-latency communication for every platform. From Engine.IO 6.6.0 until 6.6.10, a transport upgrade can independently derive an Engine.IO protocol revision from the upgrade request instead of enforcing the revision stored on the existing session. A malicious client can establish a valid session and send an upgrade request with a different or omitted EIO query parameter, attaching a transport with incompatible parser and heartbeat behavior. A crafted heartbeat packet can then trigger an uncaught exception and terminate the Node.js process, including when Engine.IO v3 compatibility is disabled because an omitted EIO value is interpreted as revision 3 on the affected path. This issue is fixed in Engine.IO 6.6.10."}], "source": {"advisory": "GHSA-2gc4-cqfq-p2gv", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "socket.io", "vendor": "socketio", "versions": [{"status": "affected", "version": ">= 6.6.0, < 6.6.10"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Socket.IO enables bidirectional and low-latency communication for every platform. From Engine.IO 6.6.0 until 6.6.10, a transport upgrade can independently derive an Engine.IO protocol revision from the upgrade request instead of enforcing the revision stored on the existing session. A malicious client can establish a valid session and send an upgrade request with a different or omitted EIO query parameter, attaching a transport with incompatible parser and heartbeat behavior. A crafted heartbeat packet can then trigger an uncaught exception and terminate the Node.js process, including when Engine.IO v3 compatibility is disabled because an omitted EIO value is interpreted as revision 3 on the affected path. This issue is fixed in Engine.IO 6.6.10."}], "id": "CVE-2026-102599", "lastModified": "2026-10-13T19:25:38.150", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-10-13T19:17:49.037", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/socketio/socket.io/commit/86db1fc3db2cd315a065d64c4e48918ccf9b4729"}, {"source": "security-advisories@github.com", "url": "https://github.com/socketio/socket.io/releases/tag/engine.io@6.6.10"}, {"source": "security-advisories@github.com", "url": "https://github.com/socketio/socket.io/security/advisories/GHSA-2gc4-cqfq-p2gv"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-248"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}