Openwebmail in cPanel 5.0, when run using suid Perl, adds the directory in the SCRIPT_FILENAME environment variable to Perl's @INC include array, which allows local users to execute arbitrary code by modifying SCRIPT_FILENAME to reference a directory containing a malicious openwebmail-shared.pl executable.
Cross-site scripting (XSS) vulnerability in cPanel 6.4.2 allows remote attackers to insert arbitrary HTML and possibly gain cPanel administrator privileges via script in a URL that is logged but not properly quoted when displayed via the (1) Error Log or (2) Latest Visitors screens.