This High severity DoS (Denial of Service) 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, and 10.3.0 of Bitbucket Data Center.

This DoS (Denial of Service) 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 cause a resource to be unavailable for its intended users by temporarily or indefinitely disrupting services of a host connected to a network which has no impact to confidentiality, no impact to integrity, high impact to availability, and requires no user interaction.

Atlassian recommends that Bitbucket 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:

• Bitbucket Data Center 9.4: Upgrade to a release greater than or equal to 9.4.21

• Bitbucket Data Center 10.2: Upgrade to a release greater than or equal to 10.2.4

• Bitbucket Data Center 10.3: Upgrade to a release greater than or equal to 10.3.1

See the release notes (https://confluence.atlassian.com/bitbucketserver/release-notes). You can download the latest version of Bitbucket Data Center from the download center (https://www.atlassian.com/software/bitbucket/download-archives).

The National Vulnerability Database provides the following description for this vulnerability: Allocation of Resources Without Limits or Throttling vulnerability in Apache Tomcat.

This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.0.M1 through 9.0.117.
Older, unsupported versions may also be affected.

Users are recommended to upgrade to version [FIXED_VERSION], which fixes the issue.