CVE-2026-42585

Name: CVE-2026-42585
Creator: NVD / NIST
Published: 2026-05-13T19:17:24.187+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 0.25%

Last modified Jun 17, 2026

CVE-2026-42585 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty incorrectly parses malformed Transfer-Encoding, enabling request smuggling attacks. EPSS estimates a 0.25% chance of exploitation in the next 30 days.

Description

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty incorrectly parses malformed Transfer-Encoding, enabling request smuggling attacks. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS Probability

0.25%

16.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-444

Affected Software

Vendor	Product	Versions
Netty	Netty	< 4.1.133
Netty	Netty	>= 4.2.0, < 4.2.13

References

https://github.com/netty/netty/security/advisories/GHSA-38f8-5428-x5cvExploit, Vendor Advisory
https://github.com/netty/netty/security/advisories/GHSA-38f8-5428-x5cvExploit, Vendor Advisory

Timeline

Published: May 13, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-42585?

How severe is CVE-2026-42585?

CVE-2026-42585 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.25% probability of exploitation in the next 30 days.

How do I fix CVE-2026-42585?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-42585?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST