CVE-2026-42584
Netty: HttpClientCodec response desynchronization
Description
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, 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. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.
INFO
Published Date :
May 13, 2026, 7:17 p.m.
Last Modified :
May 18, 2026, 12:15 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update Netty to 4.2.13.Final or 4.1.133.Final.
- Apply vendor patches if available.
- Review network request/response handling logic.
Public PoC/Exploit Available at Github
CVE-2026-42584 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-42584.
| URL | Resource |
|---|---|
| https://github.com/netty/netty/security/advisories/GHSA-57rv-r2g8-2cj3 | Exploit Vendor Advisory |
| https://github.com/netty/netty/security/advisories/GHSA-57rv-r2g8-2cj3 | Exploit Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-42584 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-42584
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Pizza on Dapr — Spring Boot 4 three-service reference: pub/sub, state, service invocation, Testcontainers + KinD e2e on cloud-provider-kind LB, multi-arch GHCR + cosign keyless OIDC
cloud-native dapr java k8 kubernetes
Java JavaScript CSS HTML Makefile Shell
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-42584 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-42584 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
May. 18, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H Added CPE Configuration OR *cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* versions up to (excluding) 4.1.133 *cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* versions from (including) 4.2.0 up to (excluding) 4.2.13 Added Reference Type CISA-ADP: https://github.com/netty/netty/security/advisories/GHSA-57rv-r2g8-2cj3 Types: Exploit, Vendor Advisory Added Reference Type GitHub, Inc.: https://github.com/netty/netty/security/advisories/GHSA-57rv-r2g8-2cj3 Types: Exploit, Vendor Advisory -
New CVE Received by [email protected]
May. 13, 2026
Action Type Old Value New Value Added Description Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, 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. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L Added CWE CWE-444 Added Reference https://github.com/netty/netty/security/advisories/GHSA-57rv-r2g8-2cj3 -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
May. 13, 2026
Action Type Old Value New Value Added Reference https://github.com/netty/netty/security/advisories/GHSA-57rv-r2g8-2cj3