Inconsistent interpretation of HTTP requests in Netty - CVE-2026-42581
Published: May 5, 2026
Vulnerability identifier: #VU130214
CSH Severity: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-42581
CWE-ID: CWE-444
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Netty
Netty
Software vendor:
Netty project
Netty project
Description
The vulnerability allows a remote attacker to perform request smuggling.
The vulnerability exists due to improper input validation in HttpObjectDecoder when processing HTTP/1.0 requests containing both Transfer-Encoding: chunked and Content-Length headers. A remote attacker can send a specially crafted HTTP/1.0 request to perform request smuggling.
Exploitation requires Netty to be deployed behind a downstream proxy or handler that trusts Content-Length over Transfer-Encoding.
Remediation
Install security update from vendor's website.