GitHub Advisoryadvisory · npm

GHSA-jfrq-hj9f-c8qx CleverTap Web SDK is vulnerable to DOM-based Cross-Site Scripting (XSS) via window.postMessage

HIGH Published 2026-02-27 Modified 2026-03-01 Official page ↗
Aliases
CVE-2026-26862
Ecosystem
npm
Packages
clevertap-web-sdk
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L
Weaknesses
CWE-79
Reviewed
2026-03-01

Affected packages

• npm clevertap-web-sdk: < 1.15.3 → fixed in 1.15.3

Description

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.

Related

Alias · CVE (1)

  • CVE-2026-26862 CleverTap Web SDK version 1.15.2 and earlier is vulnerable to DOM-based Cross-Site Scripting (XSS) via window.postMessage in the Visual… vulnerability

Weakness · CWE (1)

  • CWE-79 Improper Neutralization of Input During Web Page Generation weakness

References