BookStack prior to version 21.11.3 is vulnerable to Improper Access Control. A logged-in user with no privileges OR guest user (if public access enabled) can access the /search/users/select AJAX endpoint meant for admins to manage audit logs, to dump all usernames existing in the Bookstack database. This can also be used to harvest email belonging to a user because BookStack also uses the code where(email
, like
, %
. $search . %
) to search for users based on email.
{ "nvd_published_at": "2021-12-15T20:15:00Z", "github_reviewed_at": "2021-12-16T15:36:38Z", "severity": "MODERATE", "github_reviewed": true, "cwe_ids": [ "CWE-284" ] }