The subdomain validation bypass vulnerability, CVE-2023-49104, can be addressed by hardening the validation code in the oauth2 app. As a workaround, it is possible to disable the "Allow Subdomains" option to disable the vulnerability. File-sharing solutions have been actively targeted by threat actors in the past and this year, the Clop hacking group conducted two mass attacks on file-sharing solutions, Fortra's GoAnywhere MFT and Progress Software's MOVEit Transfer. The recommended mitigations should therefore be applied immediately.