Everybody using WinRAR must install the latest version as soon as possible.
ALL older versions are vulnerable and can lead in malware infestations.
You can get the latest version here : https://ninite.com/winrar/ (clean installer)
or from the WinRAR site : https://www.win-rar.com

If you can't update, it's safer to uninstall it.

Electro, March 2019