PHP remote file inclusion vulnerability in functions/plugin.php in SquirrelMail 1.4.6 and earlier, if register_globals is enabled and magic_quotes_gpc is disabled, allows remote attackers to execute arbitrary PHP code via a URL in the plugins array parameter. NOTE: this issue has been disputed by third parties, who state that Squirrelmail provides prominent warnings to the administrator when register_globals is enabled. Since the varieties of administrator negligence are uncountable, perhaps this type of issue should not be included in CVE. However, the original developer has posted a security advisory, so there might be relevant real-world environments under which this vulnerability is applicable

options_identities.php in SquirrelMail 1.4.4 and earlier uses the extract function to process the $_POST variable, which allows remote attackers to modify or read the preferences of other users, conduct cross-site scripting XSS) attacks, and write arbitrary files.

Cross-site scripting (XSS) vulnerability in webmail.php in SquirrelMail before 1.4.4 allows remote attackers to inject arbitrary web script or HTML via certain integer variables.

PHP remote file inclusion vulnerability in webmail.php in SquirrelMail before 1.4.4 allows remote attackers to execute arbitrary PHP code by modifying a URL parameter to reference a URL on a remote web server that contains the code.