The requests to servers to obtain the ICS files can be used to direct to any source - this is generally intended but might be a problem in certain settings.
A problematic example setting is that the service can be publicly accessible but behind a firewall. Other services run behind the same firewall. Through OWC, these services can be accessed via a GET request by the public without the firewall checking the requests.
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Requests should be restricted:
Tracking issue for:
See also
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