On Wed, 20 Jul 2011 05:07:05 +0200, Boris Zbarsky <bzbar...@mit.edu> wrote:
That said, I'm not sure I understand the security concern. What kind of whitelist-based filter would let through <script>s whose URIs it does not control, exactly? Can the security concern be mitigated by only allowing <base> outside <head> if the base URI it sets is same-origin with the document?
The <script> is from the page itself and uses a relative URL. The <base> is inserted by the attacker and causes the script to be requested from a server under the attacker's control.
-- Anne van Kesteren http://annevankesteren.nl/
