SquirrelMail 1.2.7 and earlier allows remote attackers to determine the absolute pathname of the options.php script via a malformed optpage file argument, which generates an error message when the file cannot be included in the script.

SquirrelMail 1.2.5 and earlier allows authenticated SquirrelMail users to execute arbitrary commands by modifying the THEME variable in a cookie.

load_prefs.php and supporting include files in SquirrelMail 1.0.4 and earlier do not properly initialize certain PHP variables, which allows remote attackers to (1) view sensitive files via the config_php and data_dir options, and (2) execute arbitrary code by using options_order.php to upload a message that could be interpreted as PHP.