Acrobat Reader DC versions 2020.012.20048 (and earlier), 2020.001.30005 (and earlier) and 2017.011.30175 (and earlier) and Adobe Acrobat Pro DC 2017.011.30175 (and earlier) are affected by an improper input validation vulnerability that could result in arbitrary JavaScript execution in the context of the current user. To exploit this issue, an attacker must acquire and then modify a certified PDF document that is trusted by the victim. The attacker then needs to convince the victim to open the document.