CVE-2026-42584

Publication date 13 May 2026

Last updated 8 June 2026

Ubuntu priority

Cvss 3 Severity Score

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.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
netty	26.04 LTS resolute	Fixed 1:4.1.48-16ubuntu0.1~esm2
	25.10 questing	Vulnerable
	24.04 LTS noble	Fixed 1:4.1.48-9ubuntu0.1+esm3
	22.04 LTS jammy	Fixed 1:4.1.48-4+deb11u2ubuntu0.1+esm3
	20.04 LTS focal	Fixed 1:4.1.45-1ubuntu0.1~esm6
	18.04 LTS bionic	Fixed 1:4.1.7-4ubuntu0.1+esm6
	14.04 LTS trusty	Fixed 1:3.2.6.Final-2+deb8u2ubuntu0.1~esm1

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Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
netty	Upstream: 6f69dc9

Severity score breakdown

Parameter	Value
Base score	7.3 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	Low
Integrity impact	Low
Availability impact	Low
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

References

Related Ubuntu Security Notices (USN)

USN-8401-1
Netty vulnerabilities
8 June 2026