Roundcube 1.5.x before 1.5.6 and 1.6.x before 1.6.5 allows XSS via a Content-Type or Content-Disposition header (used for attachment preview or download).
{
    "cpes": [
        "cpe:2.3:a:roundcube:webmail:*:*:*:*:*:*:*:*"
    ],
    "severity": "Medium"
}