{"api_version":"1","generated_at":"2026-06-22T12:40:26+00:00","cve":"CVE-2026-45416","urls":{"html":"https://cve.report/CVE-2026-45416","api":"https://cve.report/api/cve/CVE-2026-45416.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-45416","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-45416"},"summary":{"title":"Netty: SNI handler pre-allocates up to 16 MiB from nine attacker bytes","description":"Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, SslClientHelloHandler.decode() reads the 24-bit TLS handshake length and, when the ClientHello does not fit in the first record, eagerly allocates `ctx.alloc().buffer(handshakeLength)` (line 161). The guard at line 140 is `handshakeLength > maxClientHelloLength && maxClientHelloLength != 0`, and the commonly-used SniHandler/AbstractSniHandler constructors (SniHandler(Mapping), SniHandler(AsyncMapping), AbstractSniHandler()) pass maxClientHelloLength=0 and handshakeTimeoutMillis=0, so the length guard is disabled and no timeout is scheduled. A 16 MiB request exceeds the default pooled chunk size and becomes a huge/unpooled allocation performed immediately. The buffer is retained in the handler until the channel closes. 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