CleverTap Web SDK version 1.15.2 and earlier is vulnerable to DOM-based Cross-Site Scripting (XSS) via window.postMessage in the Visual Builder module. The origin validation in src/modules/visualBuilder/pageBuilder.js (lines 56-60) uses the includes() method to verify the originUrl contains "dashboard.clevertap.com", which can be bypassed by an attacker using a crafted subdomain.
{
"github_reviewed": true,
"github_reviewed_at": "2026-03-01T01:26:39Z",
"cwe_ids": [
"CWE-79"
],
"severity": "HIGH",
"nvd_published_at": "2026-02-27T18:16:12Z"
}