CVE-2026-26861HIGH 8.3EPSS p7.8%

CVE-2026-26861CVE-2026-26861

Description

CleverTap Web SDK version 1.15.2 and earlier is vulnerable to Cross-Site Scripting (XSS) via window.postMessage. The handleCustomHtmlPreviewPostMessageEvent function in src/util/campaignRender/nativeDisplay.js performs insufficient origin validation using the includes() method, which can be bypassed by an attacker using a subdomain

Scoring

CVSS 3.18.3 (HIGH)
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L
EPSS0.18% probability of exploitation · percentile 7.8% · 2026-06-19T12:03:05Z
Published2026-02-27
Last modified2026-03-03

Underlying weaknesses· 1

CWE-346

References

  1. https://github.com/CleverTap/clevertap-web-sdk/blob/cf1b65d/src/util/campaignRender/nativeDisplay.js#L118-L121
  2. https://github.com/CleverTap/clevertap-web-sdk/issues/424
  3. https://github.com/CleverTap/clevertap-web-sdk/pull/417

1

TypeTargetConfidenceTier
WeaknessOrigin Validation Errorcwe-3460%live

Related by meaning· 6

Nearest entities by semantic similarity across the cs-graph corpus.

CVE
CVE-2026-26862
CVE
CVE-2026-11214
CVE
CVE-2026-11242
CVE
CVE-2026-11691
CVE
CVE-2026-11129
CVE
CVE-2026-11200
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.