CVE-2026-26862

DOM‑based Cross‑Site Scripting via Window.postMessage in CleverTap Web SDK Visual Builder

Published Feb 27, 2026 CVSS 3.1 · 8.3 High EPSS < 1% KEV · Not listed
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

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-jfrq-hj9f-c8qx CleverTap Web SDK is vulnerable to DOM-based Cross-Site Scripting (XSS) via window.postMessage
History
Type Values Removed Values Added
Title DOM‑based Cross‑Site Scripting via Window.postMessage in CleverTap Web SDK Visual Builder
Type Values Removed Values Added
First Time appeared Clevertap clevertap Web Sdk
CPEs cpe:2.3:a:clevertap:clevertap_web_sdk:*:*:*:*:*:*:*:*
Vendors & Products Clevertap clevertap Web Sdk
Type Values Removed Values Added
First Time appeared Clevertap
Clevertap web Sdk
Vendors & Products Clevertap
Clevertap web Sdk
Type Values Removed Values Added
Weaknesses CWE-79
CWE-829
Metrics cvssV3_1

{'score': 8.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Feb 27, 2026, 7:39 PM
Reserved
Feb 16, 2026, 12:00 AM
Status
Analyzed
Published
Feb 27, 2026, 6:16 PM
Modified
Jun 17, 2026, 10:26 AM