HAX CMS helps manage microsite universe with PHP or NodeJs backends. Starting in version 9.0.1 and prior to version 26.0.0 of @haxtheweb/open-apis, multiple functions conduct substring-only matching to validate hostnames to which basic authorization should be sent. An attacker can append the matched substrings to an attacker-controlled endpoint and capture authentication. Version 26.0.0 fixes the issue.