TWebUpdate & TMS Subscription Manager both use Wininet.dll for http & ftp transport. Apparently, something has broken wininet.dll in these KBs. As a workaround we'd suggest to deploy with your apps a working wininet.dll.
As it is very hard to recreate the machine setup for this particular error, perhaps you could send us such a broken wininet.dll so we can test with it and see if there is a workaround (without any guarantee it can be workarounded with a broken DLL)