I am on vacation, I got this notice from GitHub:
high severity Vulnerable versions: >= 4.1.0, < 4.1.2 Patched version: 4.1.2 Versions of handlebars prior to 4.0.14 are vulnerable to Prototype Pollution. Templates may alter an Objects' prototype, thus allowing an attacker to execute arbitrary code on the server.
Vulnerability data by WhiteSource