HIGH8.3
GHSA-jfrq-hj9f-c8qx
CleverTap Web SDK is vulnerable to DOM-based Cross-Site Scripting (XSS) via window.postMessage
Quick fix
GHSA-jfrq-hj9f-c8qx — clevertap-web-sdk: upgrade to the fixed version with the command below.
npm install clevertap-web-sdk@1.15.3Details
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.
Are you affected?
Enter the version of the package you're using.
Affected packages
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-26862[ADVISORY]
- https://github.com/CleverTap/clevertap-web-sdk/issues/442[WEB]
- https://github.com/CleverTap/clevertap-web-sdk/pull/417[WEB]
- https://github.com/CleverTap/clevertap-web-sdk/commit/766f75f0c9082a27eb0b59c9fa4b0d9b19ba3d10[WEB]
- https://github.com/CleverTap/clevertap-web-sdk/commit/84695b726a751614ddc3a4f71382c239c5833e03[WEB]
- https://github.com/CleverTap/clevertap-web-sdk[PACKAGE]
- https://github.com/CleverTap/clevertap-web-sdk/blob/cf1b65d/src/modules/visualBuilder/pageBuilder.js#L56-L60[WEB]