This High severity DoS (Denial of Service) vulnerability was introduced in version 7.1.0 of Crowd Data Center and Server.

This Improper Authorization 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:N/A:H allows an unauthenticated attacker to expose assets in your environment susceptible to exploitation which has no impact to confidentiality, no impact to integrity, high impact to availability, and requires no user interaction.

Atlassian recommends that Crowd 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:

• Crowd Data Center and Server 7.1: Upgrade to a release greater than or equal to 7.1.1

See the release notes (https://www.atlassian.com/software/crowd/download-archive). You can download the latest version of Crowd Data Center from the download center (https://www.atlassian.com/software/crowd/download-archive).

The National Vulnerability Database provides the following description for this vulnerability: Improper Resource Shutdown or Release vulnerability in Apache Tomcat made Tomcat vulnerable to the made you reset attack. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.9, from 10.1.0-M1 through 10.1.43 and from 9.0.0.M1 through 9.0.107. Older, EOL versions may also be affected. Users are recommended to upgrade to one of versions 11.0.10, 10.1.44 or 9.0.108 which fix the issue.