CVE-2019-16869High· 7.5▾ TwilightNetty before 4.1.42.Final mishandles whitespace before the colon in HTTP headers (such as a "Transfer-Encoding : chunked" line), which leads to HTTP request smuggling.
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 41.3 · likelihood 1.7 · exploitation 0
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Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
8.4%
Netty before 4.1.42.Final mishandles whitespace before the colon in HTTP headers (such as a "Transfer-Encoding : chunked" line), which leads to HTTP request smuggling.
netty < 4.1.42debian_linux = 8.0debian_linux = 9.0debian_linux = 10.0ubuntu_linux = 18.04jboss_enterprise_application_platform = 7.2jboss_enterprise_application_platform = 7.3jboss_enterprise_application_platform = 7.4Upgrade past the affected range:
netty 4.1.42Connected by shared product, vendor, weakness, or advisory.
CVE-2019-20444Critical· 9.1HttpObjectDecoder.java in Netty before 4.1.44 allows an HTTP header that lacks a colon, which might be interpreted as a separate header with an incorrect syntax, or might be interpreted as an "invalid fold."
CVE-2019-20445Critical· 9.1HttpObjectDecoder.java in Netty before 4.1.44 allows a Content-Length header to be accompanied by a second Content-Length header, or by a Transfer-Encoding header.
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CVE-2021-21409Medium· 5.9Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients
CVE-2021-21295Medium· 5.9Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients
CVE-2026-100663High· 7.5Netty's HTTP/3 codec (io.netty:netty-codec-http3) from 4.2.2.Final through 4.2.17.Final does not special-case HTTP/1 CONNECT authority-form request-targets when converting HTTP/1 messages to HTTP/3 in HttpConversionUtil.toHttp3Headers