AUGH i feel like @SlackHQ has not thought through the edge cases of allowing users to specify arbitrary text for links in messagespic.twitter.com/9EJ7fOuvr6
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Looks like they just see if the text is a properly-formatted URL, can be defeated by unicode.
they covered a lot of bases (I tried cyrillic substitutions, and ratio symbol instead of colon), but not all! see #security on that slack we share
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