GHSA-JFRQ-HJ9F-C8QX

Vulnerability from github – Published: 2026-02-27 18:31 – Updated: 2026-03-01 01:26
VLAI?
Summary
CleverTap Web SDK is vulnerable to DOM-based Cross-Site Scripting (XSS) via window.postMessage
Details

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.

Severity ?
8.3 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "clevertap-web-sdk"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.15.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-26862"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-01T01:26:39Z",
    "nvd_published_at": "2026-02-27T18:16:12Z",
    "severity": "HIGH"
  },
  "details": "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.",
  "id": "GHSA-jfrq-hj9f-c8qx",
  "modified": "2026-03-01T01:26:39Z",
  "published": "2026-02-27T18:31:06Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-26862"
    },
    {
      "type": "WEB",
      "url": "https://github.com/CleverTap/clevertap-web-sdk/issues/442"
    },
    {
      "type": "WEB",
      "url": "https://github.com/CleverTap/clevertap-web-sdk/pull/417"
    },
    {
      "type": "WEB",
      "url": "https://github.com/CleverTap/clevertap-web-sdk/commit/766f75f0c9082a27eb0b59c9fa4b0d9b19ba3d10"
    },
    {
      "type": "WEB",
      "url": "https://github.com/CleverTap/clevertap-web-sdk/commit/84695b726a751614ddc3a4f71382c239c5833e03"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/CleverTap/clevertap-web-sdk"
    },
    {
      "type": "WEB",
      "url": "https://github.com/CleverTap/clevertap-web-sdk/blob/cf1b65d/src/modules/visualBuilder/pageBuilder.js#L56-L60"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "CleverTap Web SDK is vulnerable to DOM-based Cross-Site Scripting (XSS) via window.postMessage"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.