CVE-2026-9729

Web Push Notifications <= 4.39.0 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'webpushr_notification_title' Post Meta Parameter

2026-07-22 18:44
Muhammad Yudha - DJ

Strategic Overview

Status
Unpatched
Affected Version
<= 4.39.0
CVSS
6.4Medium
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2026-9729
View all Web Push Notifications – Webpushr vulnerabilities

At a glance

CVE-2026-9729 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Web Push Notifications WordPress plugin, affecting versions <= 4.39.0. It carries a CVSS score of 6.4 (reachable over the network; low attack complexity). Exploitation requires an authenticated account at Contributor level or above. No fixed release has been reported yet; treat installations running this software as exposed. Disclosed July 2026, reported by Muhammad Yudha - DJ.

Vulnerability Overview

The Webpushr Push Notifications plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'webpushr_notification_title' and 'webpushr_notification_body' parameters in versions up to, and including, 4.39.0. This is due to insufficient input sanitization in the save_send_notification_flag() function and missing output escaping in the wpp_notification_box() function, which concatenates raw post meta values directly into HTML attribute and textarea contexts. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

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')

Web Push Notifications <= 4.39.0 carries this weakness at webpushr_notification_title, and reaching it takes an account at Contributor 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. No fixed build of this plugin is recorded for Web Push Notifications yet, so installs running <= 4.39.0 stay exposed until the vendor ships one.

Remediation

No known patch available. Please review the vulnerability's details in depth and employ mitigations based on your organization's risk tolerance. It may be best to uninstall the affected software and find a replacement.

How does WordSec protect against this?

An attacker needs Contributor 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. No patched version is recorded yet, which is the case where a filtering layer matters most, because there is nothing to update to.

  • Firewall
  • Alerts

External References

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C