io.netty:netty-handler@4.1.53.Final vulnerabilities

io.netty:netty-handler is a library that provides an asynchronous event-driven network application framework and tools for rapid development of maintainable high performance and high scalability protocol servers and clients. In other words, Netty is a NIO client server framework which enables quick and easy development of network applications such as protocol servers and clients. It greatly simplifies and streamlines network programming such as TCP and UDP socket server.

Affected versions of this package are vulnerable to Denial of Service (DoS) such that if the user has no idle timeout handler configured it might be possible for a remote peer to send a client hello packet which leads the server to buffer up to 16MB of data per connection.

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.

Note:

An attacker can craft a packet that makes the SslClientHelloHandler to:

1. Allocate a 16MB ByteBuf.

2. Not fail decode method in buffer.

3. Get out of the loop without an exception.

The combination of this without the use of a timeout makes it easy to connect to a TCP server and allocate 16MB of heap memory per connection.

Upgrade io.netty:netty-handler to version 4.1.94.Final or higher.

io.netty:netty-handler is a library that provides an asynchronous event-driven network application framework and tools for rapid development of maintainable high performance and high scalability protocol servers and clients. In other words, Netty is a NIO client server framework which enables quick and easy development of network applications such as protocol servers and clients. It greatly simplifies and streamlines network programming such as TCP and UDP socket server.

Affected versions of this package are vulnerable to Information Disclosure via the AbstractDiskHttpData method, and on Unix-like systems.

When netty's multipart decoders are used, local information disclosure can occur via the local system temporary directory if temporary storing uploads on the disk are enabled. On unix-like systems, the temporary directory is shared between all users. As such, writing to this directory using API's that do not explicitly set the file/directory permissions can lead to information disclosure. The method File.createTempFile on unix-like systems creates a random file, but, by default will create this file with the permissions -rw-r--r--. Sensitive information is written to this file in AbstractDiskHttpData, and other local users can read it.

Upgrade io.netty:netty-handler to version 4.1.59.Final or higher.