{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-44894", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-05-07T21:50:33.545Z", "datePublished": "2026-06-12T14:06:54.213Z", "dateUpdated": "2026-06-12T14:06:54.213Z"}, "containers": {"cna": {"title": "Netty's Default QUIC token handler accepts any client-supplied token", "problemTypes": [{"descriptions": [{"cweId": "CWE-940", "lang": "en", "description": "CWE-940: Improper Verification of Source of a Communication Channel", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/netty/netty/security/advisories/GHSA-cmm3-54f8-px4j", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/netty/netty/security/advisories/GHSA-cmm3-54f8-px4j"}, {"name": "https://github.com/netty/netty/releases/tag/netty-4.2.15.Final", "tags": ["x_refsource_MISC"], "url": "https://github.com/netty/netty/releases/tag/netty-4.2.15.Final"}], "affected": [{"vendor": "netty", "product": "netty", "versions": [{"version": ">= 4.2.0.Final, < 4.2.15.Final", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-06-12T14:06:54.213Z"}, "descriptions": [{"lang": "en", "value": "Netty is a network application framework for development of protocol servers and clients. NoQuicTokenHandler is the tokenHandler used when the application does not set one. Prior to version 4.2.15.Final, its writeToken() returns false (server will not send Retry \u2014 acceptable), but validateToken() unconditionally `return 0`. In QuicheQuicServerCodec.handlePacket(), a non-negative return from validateToken() is interpreted as 'token is valid, ODCID starts at offset 0', causing the server to call quiche_accept as if the client's address had been validated by a Retry round-trip. Per RFC 9000 \u00a78.1, a validated address lifts the 3\u00d7 anti-amplification send limit. Thus any attacker who includes ANY non-empty token bytes in an Initial packet \u2014 with a spoofed victim source IP \u2014 causes the Netty server to treat the victim as validated and reflect full-size handshake flights (certificates, etc.) toward it without the 3\u00d7 cap. The correct 'no token handler' semantics would be to return -1 (invalid) so the normal un-validated path and amplification limit apply. Version 4.2.15.Final patches the issue."}], "source": {"advisory": "GHSA-cmm3-54f8-px4j", "discovery": "UNKNOWN"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "Netty is a network application framework for development of protocol servers and clients. NoQuicTokenHandler is the tokenHandler used when the application does not set one. Prior to version 4.2.15.Final, its writeToken() returns false (server will not send Retry \u2014 acceptable), but validateToken() unconditionally `return 0`. In QuicheQuicServerCodec.handlePacket(), a non-negative return from validateToken() is interpreted as 'token is valid, ODCID starts at offset 0', causing the server to call quiche_accept as if the client's address had been validated by a Retry round-trip. Per RFC 9000 \u00a78.1, a validated address lifts the 3\u00d7 anti-amplification send limit. Thus any attacker who includes ANY non-empty token bytes in an Initial packet \u2014 with a spoofed victim source IP \u2014 causes the Netty server to treat the victim as validated and reflect full-size handshake flights (certificates, etc.) toward it without the 3\u00d7 cap. The correct 'no token handler' semantics would be to return -1 (invalid) so the normal un-validated path and amplification limit apply. Version 4.2.15.Final patches the issue."}], "id": "CVE-2026-44894", "lastModified": "2026-06-12T15:16:26.240", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "[email protected]", "type": "Secondary"}]}, "published": "2026-06-12T15:16:26.240", "references": [{"source": "[email protected]", "url": "https://github.com/netty/netty/releases/tag/netty-4.2.15.Final"}, {"source": "[email protected]", "url": "https://github.com/netty/netty/security/advisories/GHSA-cmm3-54f8-px4j"}], "sourceIdentifier": "[email protected]", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-940"}], "source": "[email protected]", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[4.2.0.Final,4.2.15.Final)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "netty", "source": "cna", "vendor": "netty"}, "product": "netty", "vendor": "netty"}], "created": "2026-06-12T15:30:31.463347+00:00", "updated": "2026-06-12T15:30:31.796668+00:00", "vendors": ["netty", "netty$PRODUCT$netty"]}