Vulnerability library
Security checkMarch 01, 2026

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

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High severitynpmclevertap-web-sdk

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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.

Recommendation

Update the clevertap-web-sdk package to the latest compatible version. Followings are version details:

  • Affected version(s): < 1.15.3
  • Patched version(s): 1.15.3

References

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See something that needs correcting? Let us knowUpdated March 01, 2026