CVE-2023-34462

CVE-2023-34462 · netty-handler SniHandler 16MB allocation

This page contains facts from public vulnerability sources. Check the original advisory before updating.

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 timeout, it can be used to make a TCP server using the `SniHandler` to allocate 16MB of heap. The `SniHandler` class is a handler that waits for the TLS handshake to configure a `SslHandler` according to the indicated server name by the `ClientHello` record. For this matter it allocates a `ByteBuf` using the value defined in the `ClientHello` record. Normally the value of the packet should be smaller than the handshake packet but there are not checks done here and the way the code is written, it is possible to craft a packet that makes the `SslClientHelloHandler`. This vulnerability has been fixed in version 4.1.94.Final.

CVSS 6.5 · Medium · EPSS 2.5% · Fix available

Published

2023-06-22T23:00:12.104Z

Updated

2025-02-13T16:55:36.190Z

Stack: system

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