CVE-2021-39125

Affected versions of Atlassian Jira Server and Data Center allow anonymous remote attackers to discover the usernames of users via an enumeration vulnerability in the password reset page. The affected versions are before version 8.5.10, and from version 8.6.0 before 8.13.1...

The vulnerability exists in the standalone and also in the online demonstration enviroment.

It is possible to anonymously enumerate all usernames via the script at /rest/prototype/1/search/user.json?max-results=10&query=XX. The 'query' GET parameter should contain at least two charakters. It is possible to enumerate all usernames by performing a search from 'query' value 'aa' to 'zz'...