Versions of mustache prior to 2.2.1 are affected by a cross-site scripting vulnerability when attributes in mustache templates are not quoted.
Template:
<a href={{foo}}/>
Input:
{ 'foo' : 'test.com onload=alert(1)'}
Rendered result:
<a href=test.com onload=alert(1)/>
Update to version 2.2.1 or later. Alternatively, ensure that all attributes in hmustache templates are encapsulated with quotes.
{
"nvd_published_at": null,
"github_reviewed": true,
"cwe_ids": [
"CWE-79"
],
"severity": "HIGH",
"github_reviewed_at": "2020-06-16T21:59:24Z"
}