Imgur · Report #91604
Crossdomain.xml settings on api.imgur.com too open
Validstatus
2upvotes
9 Dec 2015disclosed
Summary
The crossdomain.xml file hosted at http://api.imgur.com/crossdomain.xml was too open. This allowed SWF files to make HTTP requests and see it's response. If this was not changed, then attacker.com can embed a SWF on attacker.com/example.html that makes an HTTP request to http://api.imgur.com/. The result page for http://api.imgur.com/ would include the CSRF token and the SWF file could make requests with the user's cookies.
How it was found
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