Lob - Old WebKit HTML agent in Template Preview function has multiple known vulnerabilities leading to RCE
HackerOne bug report to Lob: The Template Preview function allows users to render arbitrary HTML to a PDF document, this includes the ability to execute arbitrary Javascript. The HTML agent used to render the HTML is based on an old version of WebKit which has known security issues, for which public exploits and Proof of Concepts (PoCs) are available.