This solution applies to all Barracuda Web Security Gateway, firmware version 4.5.0.001 and earlier.
Answer:The Ultrasurf scanner that was included with firmware version 4.5.0.001 and earlier could potentially blacklist the DNS server's IP addresses, thus preventing further web access through the Web Security Gateway. The issue has been identified and fixed in firmware version 6.0.0.011 and later releases.
Web Security Gateways running firmware 4.5.0.001 will need to be patched by Technical Support. Older firmware will need to be updated to 4.5.0.001 first, before applying the patch.
No further actions required for firmware version 6.0.0.011 and later.
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