CVE-2026-75596 Netty: Fragmented ClientHello records trigger quadratic pre-handshake reassembly in default SNI parsing

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...

CVE-2026-45416

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...

CVE-2026-45416 Netty: SNI handler pre-allocates up to 16 MiB from nine attacker bytes

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...

CVE-2026-45416 Netty: SNI handler pre-allocates up to 16 MiB from nine attacker bytes

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...

CVE-2026-45416

Netty CVE-2026-45416 affects pre-4.1.135.Final and pre-4.2.15.Final versions. In SslClientHelloHandler.decode(), the 24-bit TLS handshake length is read and, if a ClientHello does not fit in the first record, Netty eagerly allocates ctx.alloc().buffer(handshakeLength). If maxClientHelloLength is ...

CVE-2026-45416 Netty: SNI handler pre-allocates up to 16 MiB from nine attacker bytes

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...

GHSA-X4GW-5CX5-PGMH Netty: SNI handler pre-allocates up to 16 MiB from nine attacker bytes

SslClientHelloHandler.decode reads the 24-bit TLS handshake length and, when the ClientHello does not fit in the first record, eagerly allocates ctx.alloc.bufferhandshakeLength line 161. The guard at line 140 is handshakeLength maxClientHelloLength && maxClientHelloLength != 0, and the...

Security Bulletin: Vulnerabilities in Netty-codec and Netty-handler might affect IBM Storage Defender Copy Data Management

Summary IBM Storage Defender Copy Data Management can be affected by vulnerabilities in Netty-codec and Netty-handler. Vulnerabilities include an incorrect validation of special crafted packet via SslHandler can lead to a native crash, the SniHandler can allocate up to 16MB of heap for each chann...

netty: SniHandler 16MB allocation leads to OOM

A flaw was found in Netty's SniHandler while navigating TLS handshake which may permit a large heap allocation if the handler did not have a timeout configured. This issue may allow an attacker to send a client hello packet which would cause the server to buffer large amounts of data per...

netty: SniHandler 16MB allocation leads to OOM

A flaw was found in Netty's SniHandler while navigating TLS handshake which may permit a large heap allocation if the handler did not have a timeout configured. This issue may allow an attacker to send a client hello packet which would cause the server to buffer large amounts of data per...

netty: SniHandler 16MB allocation leads to OOM

A flaw was found in Netty's SniHandler while navigating TLS handshake which may permit a large heap allocation if the handler did not have a timeout configured. This issue may allow an attacker to send a client hello packet which would cause the server to buffer large amounts of data per...

netty: SniHandler 16MB allocation leads to OOM

A flaw was found in Netty's SniHandler while navigating TLS handshake which may permit a large heap allocation if the handler did not have a timeout configured. This issue may allow an attacker to send a client hello packet which would cause the server to buffer large amounts of data per...

netty: SniHandler 16MB allocation leads to OOM

A flaw was found in Netty's SniHandler while navigating TLS handshake which may permit a large heap allocation if the handler did not have a timeout configured. This issue may allow an attacker to send a client hello packet which would cause the server to buffer large amounts of data per...

SUSE CVE-2023-34462

Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. The SniHandler can allocate up to 16MB of heap for each channel during the TLS handshake. When the handler or the channel does not have an idle...

UBUNTU-CVE-2023-34462

Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. The SniHandler can allocate up to 16MB of heap for each channel during the TLS handshake. When the handler or the channel does not have an idle...

PT-2023-4868 · Netty +4 · Netty +4

Name of the Vulnerable Software and Affected Versions: Netty versions prior to 4.1.94.Final Description: The issue is related to the SniHandler class in Netty, which can allocate up to 16MB of heap for each channel during the TLS handshake. This can be exploited to cause a denial of service,...

FreeBSD : Exim -- RCE with root privileges in TLS SNI handler (61db9b88-d091-11e9-8d41-97657151f8c2)

Exim developers report : If your Exim server accepts TLS connections, it is vulnerable. This does not depend on the TLS libray, so both, GnuTLS and OpenSSL are affected. The vulnerability is exploitable by sending a SNI ending in a backslash-null sequence during the initial TLS handshake. The...