CVE-2020-5403

The vulnerability occurs when a client sends HTTP/1.1 pipelined requests over a single connection, causing the Reactor Netty HTTP server to consume an excessive amount of memory. Affects Reactor Netty 1.3.0-1.3.6, 1.1.0-1.2.18, and 1.0.52 and earlier.

In specific scenarios, Reactor Netty HTTP Server may incorrectly evaluate the remote IP address when HAProxy Protocol is enabled. In order for this to happen, the application must be configured to use HAProxy Protocol. Affects Reactor Netty 1.3.0-1.3.6, 1.1.0-1.2.18, and 1.0.52 and earlier.

In specific scenarios involving WebSocket handshake redirects to a different origin, the Reactor Netty WebSocket client may leak credentials. In order for this to happen, the HTTP client must have been explicitly configured to follow redirects. Affected versions: Reactor Netty 1.3.0 - 1.3.6, 1.1.0 - 1.2.18, and 1.0.52 and earlier.

In specific scenarios, the Reactor Netty HTTP Server may leak exception details across unrelated requests. This requires Brave Tracing to be configured. Affected versions are 1.3.0-1.3.6, 1.1.0-1.2.18, and 1.0.52 and earlier.

Reactor Netty in specific scenarios involving multiple clients with different DNS resolver configurations may incorrectly reuse a previously configured DNS resolver. Affects versions 1.3.0-1.3.6, 1.1.0-1.2.18, and 1.0.52 and earlier.

In specific scenarios involving HTTP redirects from a secure to an insecure endpoint, the Reactor Netty HTTP client may leak credentials. This requires the HTTP client to be explicitly configured to follow redirects. Affected versions: Reactor Netty 1.0.0-1.0.51, 1.1.0-1.1.35, 1.2.0-1.2.17, and 1.3.0-1.3.5.

In Reactor Netty HTTP Server, versions 1.1.x prior to 1.1.13 and versions 1.0.x prior to 1.0.39, a malicious user can send a request using a specially crafted URL that can lead to a directory traversal attack. Specifically, an application is vulnerable if Reactor Netty HTTP Server is configured to serve static resources.

Pivotal Reactor Netty, versions prior to 0.8.11, passes headers through redirects, including authorization ones. A remote unauthenticated malicious user may gain access to credentials for a different server than they have access to.