CVE-2026-75595: Netty: SNI Routing Bypass via Fragmented TLS ClientHello Causing Fallback to Default SslContext
A fragmented TLS ClientHello whose handshake header spans multiple records makes Netty silently fall back to the default SslContext; where per-SNI selection is the sole mTLS gate, an unauthenticated attacker can bypass the route’s mTLS requirement.
References
- github.com/advisories/GHSA-c4c3-7fpv-j4q5
- github.com/netty/netty/commit/1b5abc6443b63726c72cdd285af2feb7ddbb8ff7
- github.com/netty/netty/commit/9e0519239108a69b7e9bbc5e9182ee139a0d7961
- github.com/netty/netty/pull/17213
- github.com/netty/netty/pull/17217
- github.com/netty/netty/releases/tag/netty-4.1.137.Final
- github.com/netty/netty/releases/tag/netty-4.2.17.Final
- github.com/netty/netty/security/advisories/GHSA-c4c3-7fpv-j4q5
- nvd.nist.gov/vuln/detail/CVE-2026-75595
Code Behaviors & Features
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