CVE-2026-75596: fallo de gravedad alta en netty
Netty: Fragmented ClientHello records trigger quadratic pre-handshake reassembly in default SNI parsing
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
21Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 8.7epss 0.4%
Netty is an asynchronous, event-driven network application framework. Prior to 4.1.137.Final and 4.2.17.Final, the default io.netty.handler.ssl.SniHandler constructors use the pre-handshake ClientHello aggregation path in handler/src/main/java/io/netty/handler/ssl/SslClientHelloHandler.java at io.netty.handler.ssl.SslClientHelloHandler#decode, where handshakeBuffer.clear() and writeBytes() recopy all previously received body bytes for every additional TLS record. An unauthenticated remote peer can advertise a large ClientHello and deliver its body in thousands of tiny records, causing quadratic CPU work on the event loop before the TLS handshake completes and degrading TLS handling for other clients. This issue is fixed in versions 4.1.137.Final and 4.2.17.Final.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Productos afectados
netty · nettyCVEs relacionadas — netty
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Referencias
https://github.com/netty/netty/commit/1b5abc6443b63726c72cdd285af2feb7ddbb8ff7https://github.com/netty/netty/commit/9e0519239108a69b7e9bbc5e9182ee139a0d7961https://github.com/netty/netty/pull/17213https://github.com/netty/netty/pull/17217https://github.com/netty/netty/releases/tag/netty-4.1.137.Finalhttps://github.com/netty/netty/releases/tag/netty-4.2.17.Finalhttps://github.com/netty/netty/security/advisories/GHSA-fccg-mwvh-qqg4