Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:LSummary
CVE-2026-26862 is a high-severity Cross-site Scripting (CWE-79) vulnerability in Clevertap Clevertap Web Sdk. Its CVSS base score is 8.3 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Browser Session Hijacking (T1185); ranked at the 29th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CleverTap Web SDK versions 1.15.2 and earlier are affected by a DOM-based Cross-Site Scripting (XSS) vulnerability in the Visual Builder module. The issue stems from improper origin validation in src/modules/visualBuilder/pageBuilder.js (lines 56-60), where the code uses the includes() method to check if originUrl contains "dashboard.clevertap.com". This check can be bypassed by an attacker using a crafted subdomain that includes the target string.
Attackers can exploit this vulnerability remotely with low complexity and no privileges required, though user interaction is necessary, as indicated by the CVSS v3.1 base score of 8.3 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L). By hosting a malicious page on a subdomain like one incorporating "dashboard.clevertap.com" and sending a window.postMessage, an attacker can trick a user into visiting the page while the SDK is loaded, bypassing the origin check and executing arbitrary JavaScript in the victim's browser context. This enables high-impact confidentiality and integrity violations, such as stealing session tokens or sensitive data, with low availability impact.
Mitigation is addressed in the CleverTap web-sdk GitHub repository via pull request #417, which fixes the origin validation flaw. The vulnerability is documented in issue #442, and the vulnerable code snippet is available at the referenced lines in pageBuilder.js. Security practitioners should update to a patched version beyond 1.15.2.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-9039
Vulnerability Data
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…
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be bypassed by an attacker using a crafted subdomain
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 6 hardening rules · 6 OS baselines
V14.2.3V1.1.2V1.3.2V3.5.6
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation can discover missing or incorrect input neutralization through targeted web-application tests.
Input validation directly enforces neutralization of untrusted data before it reaches web output generation.
Output filtering can catch or sanitize unneutralized script content before it is served to users.
Requires documented, valid provenance for components, preventing acceptance of code from outside the trusted sphere.
Implements detection and prevention of counterfeit or inauthentic components before they are integrated.
Establishes processes to identify and address supply-chain weaknesses that would allow untrusted functionality.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Pre-acquisition integrity/authenticity checks directly prevent inclusion of untrusted code.
Supply-chain program directly governs inclusion of third-party executable code.
Contractual requirements can mandate trusted sources and integrity checks for included functionality.
Supplier risk assessment explicitly covers risks from their products and libraries.
Critical-supplier assessment reduces risk of importing executable functionality from untrusted parties.
Secure SDLC practices directly target introduction of XSS via coding standards/testing (mostly), yet the single broad outcome leaves many specific neutralization vectors unaddressed (partial).
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
By requiring suppliers to propagate security requirements and to disclose component provenance, the control limits the inclusion of functionality obtained from untrusted third-party sources without oversight.
Secure-coding testing and automated code-analysis tools are applied to detect improper neutralization of script-related content during web-page generation.
Knowledge exchange on emerging attack techniques and patches reduces the likelihood that cross-site scripting flaws remain unaddressed in deployed applications.
Operational indicators of compromise for web-application attacks can be incorporated into WAF or input-filtering rules, lowering the likelihood that unsanitized data reaches the browser.
Requiring language-specific secure-coding standards and automated scanning during the SDLC catches missing output encoding or improper neutralization of untrusted data before the software reaches production.
Secure-coding standards, SAST scans and removal of insecure code samples together eliminate the failure to neutralize script content that produces cross-site scripting flaws.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (1 rule)
- V-248635 Executable search paths within the initialization files of all local interactive OL 8 users must only contain paths that resolve to the system default or the user's home directory. prevents CWE-829
Oracle Linux 9 (1 rule)
- V-271847 OL 9 must be configured so that executable search paths within the initialization files of all local interactive users must only contain paths that resolve to the system default or the users home directory. prevents CWE-829
RHEL 7 (1 rule)
- V-204477 The Red Hat Enterprise Linux operating system must be configured so that all local interactive user initialization files executable search paths contain only paths that resolve to the users home directory. prevents CWE-829
RHEL 8 (1 rule)
- V-230317 Executable search paths within the initialization files of all local interactive RHEL 8 users must only contain paths that resolve to the system default or the users home directory. prevents CWE-829
RHEL 9 (1 rule)
- V-258050 Executable search paths within the initialization files of all local interactive RHEL 9 users must only contain paths that resolve to the system default or the users home directory. prevents CWE-829
Windows 10 (1 rule)
- V-220737 Administrative accounts must not be used with applications that access the Internet, such as web browsers, or with potential Internet sources, such as email. prevents CWE-829