XSS in Webpushr Web Push Notifications –

CVE-2026-9729

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.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.003 (25.9th percentile) — read the EPSS interpretation.