Yes, URLs like that are commonly used in phishing emails, so that's my hunch as ...

petercooper on July 8, 2015 | parent | context | favorite | on: Why does Gmail hate my domain?

Yes, URLs like that are commonly used in phishing emails, so that's my hunch as well. They're just not recognizing that such strings can appear in domains so I suspect it's a simple bug but probably not one they'll fix.