[原文]Michael Salzer Guestbox 0.6, and other versions before 0.8, allows remote attackers to post an admin comment to a guestbook entry via a certain modified form, possibly related to the nummer parameter.
Guestbox contains a flaw that may allow a malicious user to gain access to unauthorized privileges. The issue is triggered by a failure to properly authenticate HTTP requests for administrative functions in the action.php script. This flaw may lead to a loss of integrity.
Upgrade to version 0.7 BETA or higher, as it has been reported to fix this vulnerability. An upgrade is required as there are no known workarounds.