HTTP Request Smuggling Affecting io.netty:netty-codec-http package, versions [,4.1.125.Final)[4.2.0.Alpha1,4.2.5.Final)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
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-12485149
- published4 Sept 2025
- disclosed3 Sept 2025
- creditJeppe Bonde Weikop, Jonathan Leitschuh
Introduced: 3 Sep 2025
NewCVE-2025-58056 (opens in a new tab)How to fix?
Upgrade io.netty:netty-codec-http to version 4.1.125.Final, 4.2.5.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 via the parsing of chunk extensions in HTTP/1.1 messages with chunked encoding. An attacker can bypass HTTP request boundaries by sending specially crafted HTTP requests that exploit differences in how standalone newline characters are parsed between reverse proxies and the backend, potentially allowing them to smuggle additional requests.