CVE-2026-44894
highpriority · track · 0EPSS 0.001 · 4 %ileDEEUUSEPSS · scored 2026-10-27
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 — 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 §8.1, a validated address lifts the 3× anti-amplification send limit. Thus any attacker who includes ANY non-empty token bytes in an Initial packet — with a spoofed victim source IP — causes the Netty server to treat the victim as validated and reflect full-size handshake flights (certificates, etc.) toward it without the 3× 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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (23)
Products and version ranges known to be affected.
- IBM App Connect Enterprise Professionalall versionscert_bundDEcpe:/a:ibm:app_connect_enterprise:professional
- Red Hat Enterprise Linux Data Grid 8all versionscert_bundDEcpe:/o:redhat:enterprise_linux:data_grid_8
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-1814Netty: Mehrere SchwachstellenDeutsch2026-06-07csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Netty ausnutzen, um Sicherheitsvorkehrungen zu umgehen, Daten zu manipulieren, vertrauliche Informationen offenzulegen oder einen Denial-of-Service-Zustand herbeizuführen.
- GHSA-cmm3-54f8-px4jNetty's Default QUIC token handler accepts any client-supplied token2026-06-08ghsa · osvUS
NoQuicTokenHandler is the tokenHandler used when the application does not set one. Its writeToken() returns false (server will not send Retry — 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 §8.1, a validated address lifts the 3× anti-amplification send limit. Thus any attacker who includes ANY non-empty token bytes in an Initial packet — with a spoofed victim source IP — causes the Netty server to treat the victim as validated and reflect full-size handshake flights (certificates, etc.) toward it without the 3× cap. The correct 'no token handler' semantics would be to return -1 (invalid) so the normal un-validated path and amplification limit apply.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (10)
External citations — patches, advisories, analysis.
- https://github.com/netty/netty/releasesPatchcnnvd
- https://github.com/netty/netty/releases/tag/netty-4.2.15.Finalcnnvd
- https://github.com/netty/netty/security/advisories/GHSA-cmm3-54f8-px4jcnnvd
- https://github.com/netty/netty/releases/tag/netty-4.2.15.Finalenisa_euvd
- https://github.com/netty/netty/security/advisories/GHSA-cmm3-54f8-px4jenisa_euvd
- https://access.redhat.com/security/cve/CVE-2026-44894nvd
- https://bugzilla.redhat.com/show_bug.cgi?id=2488380nvd
- https://github.com/netty/netty/releases/tag/netty-4.2.15.FinalRelease Notesnvd
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