CVE-2026-13424
The Online Scheduling and Appointment Booking System – Bookly plugin for WordPress is vulnerable to Stored Cross-Site Scripting via bookly_speed_up_update_addons AJAX action in all versions up to, and including, 27.7 due to insufficient input…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.58%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
The Online Scheduling and Appointment Booking System – Bookly plugin for WordPress is vulnerable to Stored Cross-Site Scripting via bookly_speed_up_update_addons AJAX action in all versions up to, and including, 27.7 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The injection point is the bookly_speed_up_update_addons AJAX action, which is registered as wp_ajax_nopriv_* and therefore reachable without authentication; the payload is stored verbatim in the bookly_log.details column when a request is submitted without a valid signature, and executes when an administrator later views the Diagnostics → Logs page.
- CVSS 3.1
- 7.2 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
- EPSS
- 0.58% probability · 47th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Source
- security@wordfence.com
EPSS 0.6% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/27.5/backend/modules/diagnostics/Ajax.php#L344
- https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/27.5/backend/modules/diagnostics/resources/js/diagnostics.js#L542
- https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/27.5/lib/PluginsUpdater.php#L13
- https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/27.5/lib/PluginsUpdater.php#L97
- https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/27.7/backend/modules/diagnostics/Ajax.php#L344
- https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/27.7/backend/modules/diagnostics/resources/js/diagnostics.js#L542
- https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/27.7/lib/PluginsUpdater.php#L13
- https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/27.7/lib/PluginsUpdater.php#L97
- https://plugins.trac.wordpress.org/changeset?reponame=&old=3637918%40bookly-responsive-appointment-booking-tool&new=3637918%40bookly-responsive-appointment-booking-tool
- https://www.wordfence.com/threat-intel/vulnerabilities/id/cfb53e44-7f9d-490f-b938-f428c20219d7?source=cve
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.