VYPR
← All advisories
Medium severity5.8GHSA Advisory· Published May 13, 2026· Updated May 18, 2026

CVE-2026-42581

CVE-2026-42581

Description

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpObjectDecoder strips a conflicting Content-Length header when a request carries both Transfer-Encoding: chunked and Content-Length, but only for HTTP/1.1 messages. The guard is absent for HTTP/1.0. An attacker that sends an HTTP/1.0 request with both headers causes Netty to decode the body as chunked while leaving Content-Length intact in the forwarded HttpMessage. Any downstream proxy or handler that trusts Content-Length over Transfer-Encoding will disagree on message boundaries, enabling request smuggling. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

Affected packages

Versions sourced from the GitHub Security Advisory.

PackageAffected versionsPatched versions
io.netty:netty-codec-httpMaven
>= 4.2.0.Alpha1, < 4.2.13.Final4.2.13.Final
io.netty:netty-codec-httpMaven
< 4.1.133.Final4.1.133.Final

Affected products

251

Patches

Vulnerability mechanics

References

3

News mentions

0

No linked articles in our index yet.