Security Bulletin:Netty Versions 4.2.0.Final-4.2.16.Final, 4.1.136.Final: TLS Hostname Verification Disabled

Summary Netty io.netty:netty-handler versions from 4.2.0.Final through 4.2.16.Final and versions through 4.1.136.Final disable TLS hostname verification on the SslProvider.OPENSSL client path when a plain non-extended X509TrustManager is used and Unsafe-based trust-manager wrapping is unavailable...

ROOT-APP-MAVEN-CVE-2026-75595 CVE-2026-75595 in io.netty:netty-handler - Patched by Root

Root has patched CVE-2026-75595 in the io.netty:netty-handler package for Root:Maven. Multiple fixed versions available...

io.netty/netty-handler: Netty: TLS hostname verification bypass via OpenSSL client path misconfiguration

A flaw was found in Netty io.netty:netty-handler. When using the SslProvider.OPENSSL client path with a plain X509TrustManager and without Unsafe-based trust-manager wrapping Java 25+, TLS hostname verification is disabled. This misconfiguration allows a man-in-the-middle attacker to present a...

io.netty/netty-handler: Netty: TLS hostname verification bypass via OpenSSL client path misconfiguration

A flaw was found in Netty io.netty:netty-handler. When using the SslProvider.OPENSSL client path with a plain X509TrustManager and without Unsafe-based trust-manager wrapping Java 25+, TLS hostname verification is disabled. This misconfiguration allows a man-in-the-middle attacker to present a...

io.netty/netty-handler: Netty: TLS hostname verification bypass via OpenSSL client path misconfiguration

A flaw was found in Netty io.netty:netty-handler. When using the SslProvider.OPENSSL client path with a plain X509TrustManager and without Unsafe-based trust-manager wrapping Java 25+, TLS hostname verification is disabled. This misconfiguration allows a man-in-the-middle attacker to present a...

io.netty/netty-handler: Netty: TLS hostname verification bypass via OpenSSL client path misconfiguration

A flaw was found in Netty io.netty:netty-handler. When using the SslProvider.OPENSSL client path with a plain X509TrustManager and without Unsafe-based trust-manager wrapping Java 25+, TLS hostname verification is disabled. This misconfiguration allows a man-in-the-middle attacker to present a...

Denial Of Service (DoS)

io.netty:netty-handler is vulnerable to Denial of Service DoS attacks. During TLS handshakes, the SniHandler class can allocate up to 16MB of heap for each channel. The SniHandler is used to establish a TCP server when the handler or channel has no idle timeout. In order to configure an SSL handl...