Server-Side Request Forgery (SSRF)
Lack of input validation of the Zendesk subdomain could expose users of the library to Server Side Request Forgery (SSRF). This was fixed in 2.2.11. All versions before 2.2.11 are vulnerable.
CWE-918 - Server-Side Request Forgery (SSRF)
Server-side request forgery (SSRF) is a weakness that allows an attacker to send an arbitrary request, making it appear that the request was sent by the server. This request may bypass a firewall that would normally prevent direct access to the URL. The impact of this vulnerability can vary from unauthorized access to files and sensitive information to remote code execution.