Advisory details:
github_osv / GHSA-57rv-r2g8-2cj3
| Advisory ID | github_osv/GHSA-57rv-r2g8-2cj3 |
| Aliases |
CVE-2026-42584
|
| Summary | Netty has HttpClientCodec response desynchronization ### Summary If HttpClientCodec is configured, there are use cases when a response body from one request, can be parsed as another's. ### Details HttpClientCodec pairs each inbound response with an outbound request by `queue.poll()` once per response, including for `1xx`. If the client pipelines GET then HEAD and the server sends 103, then 200 with GET body, then 200 for HEAD, the queue pairs HEAD with the first 200. The HEAD rule then skips reading that message’s body, so the GET entity bytes stay on the stream and the following 200 is parsed from the wrong offset. Prerequisites - HTTP/1.1 pipelining - HEAD in the pipeline - The server sends 1xx ### PoC ```java @Test public void test() { EmbeddedChannel channel = new EmbeddedChannel(new HttpClientCodec()); assertTrue(channel.writeOutbound(new DefaultFullHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.GET, "/1"))); ByteBuf request = channel.readOutbound(); request.release(); assertNull(channel.readOutbound()); assertTrue(channel.writeOutbound(new DefaultFullHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.HEAD, "/2"))); request = channel.readOutbound(); request.release(); assertNull(channel.readOutbound()); String responseStr = "HTTP/1.1 103 Early Hints\r\n\r\n" + "HTTP/1.1 200 OK\r\nContent-Length: 5\r\n\r\nhello" + "HTTP/1.1 200 OK\r\n\r\n"; assertTrue(channel.writeInbound(Unpooled.copiedBuffer(responseStr, CharsetUtil.US_ASCII))); // Response 1 HttpResponse response = channel.readInbound(); assertEquals(HttpResponseStatus.EARLY_HINTS, response.status()); LastHttpContent last = channel.readInbound(); assertEquals(0, last.content().readableBytes()); last.release(); // Response 2 response = channel.readInbound(); assertEquals(HttpResponseStatus.OK, response.status()); last = channel.readInbound(); assertEquals(0, last.content().readableBytes()); last.release(); // Response 3 FullHttpResponse response1 = channel.readInbound(); assertTrue(response1.decoderResult().isFailure()); assertEquals(0, response1.content().readableBytes()); response1.release(); assertFalse(channel.finish()); } ``` ### Impact Integrity/availability of HTTP parsing on that connection, unsafe reuse of the socket. |
| Status | Published |
| Exploitability | 0.5 |
| Weighted Severity | 6.6 |
| Risk | 3.3 |
| Affected and Fixed Packages | Package Details |
| Introduced and Fixed Package Commit Patches | Package Commit Patches Details |
| System | Score | Found at |
|---|---|---|
| cvssv3.1 | 7.3 | https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-57rv-r2g8-2cj3/GHSA-57rv-r2g8-2cj3.json |
| generic_textual | HIGH |
| Reference id | Reference type | URL |
|---|---|---|
| https://github.com/netty/netty | ||
| CVE-2026-42584 | https://nvd.nist.gov/vuln/detail/CVE-2026-42584 | |
| GHSA-57rv-r2g8-2cj3 | Other | https://github.com/netty/netty/security/advisories/GHSA-57rv-r2g8-2cj3 |
No EPSS data available for this advisory.
| Patch URL | |
|---|---|
| There are no known patches. | |
| Attack Vector (AV) | Attack Complexity (AC) | Privileges Required (PR) | User Interaction (UI) | Scope (S) | Confidentiality Impact (C) | Integrity Impact (I) | Availability Impact (A) |
|---|---|---|---|---|---|---|---|
network adjacent_network local physical |
low high |
none low high |
none required |
unchanged changed |
high low none |
high low none |
high low none |
There are no SSVC decisions available.