PHPMailer before 6.1.6 contains an output escaping bug when the name of a file attachment contains a double quote character. This can result in the file type being misinterpreted by the receiver or any mail relay processing the message.
{
    "cpes": [
        "cpe:2.3:a:phpmailer_project:phpmailer:*:*:*:*:*:*:*:*"
    ],
    "severity": "High"
}