Someone with bad intentions exploited a previously unknown security flaw (a zero-day exploit) in imgur in order to deploy a botnet which DDoS'd 8chan (and possibly may do some more nasty things). As a result, malwarebytes blacklisted imgur. Imgur claims that it is fixed, but malwarebytes still did not lifted the ban because it doesn't seems safe yet.
Link for further details: https://forums.malwarebytes.org/index.php?/topic/173238-malwarebytes-blocking-imgur/
Since all the StackExchange / StackOverflow network is heavily dependent on imgur for images, it is not working correctly for malwarebytes users. Most of images renders as broken images since they were blocked by malwarebytes.
Now, the actual question: What is the possibility that the exploit could/would compromise SE/SO users, if any? Specially if the vulnerability is not fixed after all?