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.

Affected: Ubuntu:18.04:LTS: netty-3.9

It was discovered that Netty incorrectly handled certain HTTP headers. By sending an HTTP header with whitespace before the colon, a remote attacker could possibly use this issue to perform an HTTP request smuggling attack. (CVE-2019-16869)

It was discovered that Netty incorrectly handled certain HTTP headers. By sending an HTTP header that lacks a colon, a remote attacker could possibly use this issue to perform an HTTP request smuggling attack. (CVE-2019-20444)

It was discovered that Netty incorrectly handled certain HTTP headers. By sending a Content-Length header accompanied by a second Content-Length header, or by a Transfer-Encoding header, a remote attacker could possibly use this issue to perform an HTTP request smuggling attack. (CVE-2019-20445)