Permissions, Privileges, and Access Controls
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.
CWE-264 - Permissions Privileges and Access Controls
CWE 264 (permissions, privileges, and access controls) is not a weakness in and of itself, rather it is a category of weaknesses related to the management of permissions, privileges, and other security features used to perform access control. If not addressed, the weaknesses in this category allow attackers to gain privileges for an unintended sphere of control, access sensitive information, and execute arbitrary commands.