This High severity HTTP Request Smuggling vulnerability was introduced in versions 9.0.1, 9.2.3, and 9.4.0 of Confluence Data Center.
 
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:H/I:N/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 Confluence Data Center customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions:

• Confluence Data Center 9.2: Upgrade to a release greater than or equal to 9.2.5

 
See the release notes (https://confluence.atlassian.com/doc/confluence-release-notes-327.html). You can download the latest version of Confluence Data Center from the download center (https://www.atlassian.com/software/confluence/download-archives).
 
The National Vulnerability Database provides the following description for this vulnerability:
 
ws is an open source WebSocket client and server for Node.js. Prior to 8.20.1, the websocket.close() implementation is vulnerable to uninitialized memory disclosure when a TypedArray is passed as the reason argument. This vulnerability is fixed in 8.20.1.