This High severity DoS (Denial of Service) vulnerability was introduced in version 11.3.0 of Jira Service Management Data Center.

This 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 Jira Service Management 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:

• Jira Service Management Data Center and Server 11.3: Upgrade to a release greater than or equal to 11.3.1

See the release notes. You can download the latest version of Jira Service Management Data Center and Server from the download center.

The National Vulnerability Database provides the following description for this vulnerability: Versions of the package semver before 7.5.2 are vulnerable to Regular Expression Denial of Service (ReDoS) via the function new Range, when untrusted user data is provided as a range.