This High severity io.netty:netty-codec-http Dependency vulnerability was introduced in versions 9.0.1, 9.1.0, 9.2.0,
9.3.0, 9.4.0, 9.5.0, 9.6.0, 10.0.0, 10.1.1, 10.2.0, 10.3.0 of Bitbucket Data Center and Server.
 
This HTTP Request Smuggling vulnerability, with a CVSS Score of 7.5 and a CVSS Vector of
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N allows an unauthenticated attacker to expose assets in your environment
susceptible to exploitation which has no impact to confidentiality, high impact to integrity, no impact to availability,
and requires no user interaction.
 
Atlassian recommends that Bitbucket Data Center and Server customers upgrade to latest version, if you are unable to do
so, upgrade your instance to one of the specified supported fixed versions:

• Bitbucket Data Center 10.3: Upgrade to a release greater than or equal to 10.3.1
• Bitbucket Data Center 10.2: Upgrade to a release greater than or equal to 10.2.4
• Bitbucket Data Center 9.4: Upgrade to a release greater than or equal to 9.4.22

See the release notes (https://confluence.atlassian.com/bitbucketserver/release-notes). You can download the latest
version of Bitbucket Data Center and Server from the download center
(https://www.atlassian.com/software/bitbucket/download-archives).
 
The National Vulnerability Database provides the following description for this vulnerability:
 
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty
incorrectly parses malformed Transfer-Encoding, enabling request smuggling attacks. This vulnerability is fixed in
4.2.13.Final and 4.1.133.Final.