"WordPress
2.3.3 is an urgent security release. A flaw was found in our XML-RPC
implementation such that a specially crafted request would allow any
valid user to edit posts of any other user on that blog. In addition to
fixing this security flaw, 2.3.3 fixes a few minor bugs. If you are interested only in the security fix, download the fixed version of xmlrpc.php and copy it over your existing xmlrpc.php. Otherwise, you can get the entire release here."

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