Inconsistent interpretation of HTTP requests in Netty - CVE-2026-50020
Published: June 8, 2026
Vulnerability identifier: #VU133456
CSH Severity: Medium
CVSS v4.0: 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-2026-50020
CWE-ID: CWE-444
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Netty project
Affected software:
Netty
Netty
Detailed vulnerability description
The vulnerability allows a remote attacker to smuggle HTTP requests.
The vulnerability exists due to inconsistent interpretation of HTTP requests in HttpObjectDecoder when parsing requests with non-CRLF control characters before the request-line. A remote attacker can send a specially crafted request to smuggle HTTP requests.
The issue can cause request-boundary confusion when a front-end component interprets the prepended bytes differently in pipelined or multiplexed transports.
How to mitigate CVE-2026-50020
Install security update from vendor's website.