CVE-2026-15101

WPBakery Page Builder <= 8.7.4 - Authenticated (Subscriber+) Stored Cross-Site Scripting via 'data' Parameter

2026-08-31 21:00

Strategic Overview

Status: Patched in 9.0
Affected Plugin: WPBakery Page Builder
Affected Version: <= 8.7.4
CVSS: 6.4Medium
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2026-15101

View all WPBakery Page Builder vulnerabilities

At a glance

CVE-2026-15101 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the WPBakery Page Builder WordPress plugin, affecting versions <= 8.7.4. It carries a CVSS score of 6.4 (reachable over the network; low attack complexity). Exploitation requires an authenticated account at Subscriber level or above. The issue is fixed in version 9.0; sites on affected versions should update now. Disclosed August 2026, reported by d.v4n_s3c.

Vulnerability Overview

The WPBakery Page Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'data' parameter in all versions up to, and including, 8.7.4 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The wp_kses_post sanitization applied during save does not neutralize the payload because the malicious script content is base64-encoded as plain alphanumeric text with no HTML tags to strip; the vc_raw_html shortcode template then decodes and echoes this content unescaped at render time.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no interaction from a victim user.

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

WPBakery Page Builder <= 8.7.4 carries this weakness at data, and reaching it takes an account at Subscriber level or above. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.

Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For WPBakery Page Builder the fix is 9.0: builds <= 8.7.4 are affected, anything from 9.0 onward is not.

Remediation

Update to version 9.0, or a newer patched version

How does WordSec protect against this?

An attacker needs Subscriber access first, so the firewall sees the attempt as traffic from a logged-in account: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: WPBakery Page Builder 9.0 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-15101 https://www.wordfence.com/threat-intel/vulnerabilities/id/b61ced52-30a2-407a-8659-1ae4a4d99aab https://nvd.nist.gov/vuln/detail/CVE-2026-15101

Related records

Same weakness class

Other vulnerabilities in WPBakery Page Builder

CVSS Vector

6.4

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone

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