HTTP Request Smuggling Affecting io.netty:netty-codec-http package, versions [,4.1.135.Final)[4.2.0.Alpha1,4.2.15.Final)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-JAVA-IONETTY-17337012
- published14 Jun 2026
- disclosed12 Jun 2026
- creditUnknown
Introduced: 12 Jun 2026
NewCVE-2026-50020 (opens in a new tab)How to fix?
Upgrade io.netty:netty-codec-http to version 4.1.135.Final, 4.2.15.Final or higher.
Overview
io.netty:netty-codec-http is a network application framework for rapid development of maintainable high performance protocol servers & clients.
Affected versions of this package are vulnerable to HTTP Request Smuggling in HttpObjectDecoder.java, which skips whitespace as well as bytes 0x00-0x1F and 0x7F. An attacker can cause request-boundary confusion in pipelined or multiplexed transports by sending malicious HTTP requests containing arbitrary control characters, which may be interpreted differently by front-end components.