Inter7 SqWebMail 3.4.1 through 3.6.1 generates different error messages for incorrect passwords versus correct passwords on non-mail-enabled accounts (such as root), which allows remote attackers to guess the root password via brute force attacks.

Cross-site scripting (XSS) vulnerability in the printheaderuc function for SqWebMail 4.0.4 and earlier, and possibly 3.x, allows remote attackers to inject arbitrary web script or HRML via (1) e-mail headers or (2) a message with a "message/delivery-status" MIME Content-Type.

Cross-site scripting (XSS) vulnerability in SqWebMail 5.0.4 allows remote attackers to inject arbitrary web script or HTML via a file attachment that is processed by the Display feature. NOTE: the severity of this issue has been disputed by the developer.

Cross-site scripting (XSS) vulnerability in SqWebMail 5.0.4 allows remote attackers to inject arbitrary web script or HTML via an e-mail message containing Internet Explorer "Conditional Comments" such as "[if]" and "[endif]".

Cross-site scripting (XSS) vulnerability in SqWebMail 5.0.4 and possibly other versions allows remote attackers to inject arbitrary web script or HTML via an HTML e-mail containing tags with strings that contain ">" or other special characters, which is not properly sanitized by SqWebMail.