Mandriva Linux Security Advisory 2009-066 - PHP 4.4.4, 5.1.6, and other versions, when running on Apache, allows local users to modify behavior of other sites hosted on the same web server by modifying the mbstring.func_overload setting within.htaccess, which causes this setting to be applied to other virtual hosts on the same server. The updated packages have been patched to correct these issues.
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