AOL 9.0 Security Edition revision 4184.2340, and probably other versions, uses insecure permissions (Everyone/Full Control) for the "America Online 9.0" directory, which allows local users to gain privileges by replacing critical files.
The default configuration of the America Online (AOL) client software allows all users to modify a certain registry value that specifies a DLL file name, which might allow local users to gain privileges via a Trojan horse program.