CVE-2026-42583

A flaw was found in Netty, an asynchronous, event-driven network application framework. A remote attacker can exploit this vulnerability by sending a specially crafted LZ4 compressed data stream. This can cause the Lz4FrameDecoder to allocate a large amount of memory up to 32 MB per block before...

CVE-2026-42583: Uncontrolled Resource Consumption

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Lz4FrameDecoder allocates a ByteBuf of size decompressedLength up to 32 MB per block before LZ4 runs. A peer only needs a 21-byte header plus compressedLength payload bytes - 22 bytes if...

GHSA-6MJQ-H674-J845 netty-handler SniHandler 16MB allocation

Summary 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 timeout, it can be used to make a TCP server using the SniHandler to allocate 16MB of heap. Details The SniHandler class is a handler that waits...