Online Scheduling and Appointment Booking System <= 27.7 — Unauthenticated Stored Cross-Site Scripting via bookly_speed_up_update_addons AJAX action
CVE-2026-13424Published · Updated Action summary
Affected: ≤27.7Update to 28.0 or newer
All remediation steps- Severity
- High7.2
- CVSS
- 7.2CVSS 3.1 · CNA (Wordfence)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:NWhat does this vector mean?
AV:NAttack vector- Network
AC:LAttack complexity- Low
PR:NPrivileges required- None
UI:NUser interaction- None
S:CScope- Changed
C:LConfidentiality- Low
I:LIntegrity- Low
A:NAvailability- None
- Weakness
- CWE-79 Cross-Site Scripting
- Required access
- No account needed
- Exploit prediction (EPSS)
- No score
- CISA KEV
- Not listed
On this page8
Am I affected?
Online Scheduling and Appointment Booking System – Bookly bookly-responsive-appointment-booking-tool
- Affected≤ 27.7
- Patched in28.0
Update to 28.0 or newer.
You are affected if you run ≤ 27.7. Version 28.0 and later are not affected by this issue.
- Check your version: in wp-admin go to Plugins → Installed Plugins and read the version under Online Scheduling and Appointment Booking System – Bookly.
- No admin access? Run a passive check of your site. It reads public files only.
- No account is needed to exploit this. Treat any exposed site on an affected version as at risk.
What to do
- Update to version 28.0, or a newer patched version
- Rotate administrator passwords and application secrets if the site ran a vulnerable version while publicly reachable.
- Watch Online Scheduling and Appointment Booking System – Bookly to get an email when the next vulnerability is published.
Advisory
Source description from Wordfence Intelligence, credited to Dmitrii Ignatyev.
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.
Exploits & references
Proof-of-concept & detection
No public proof-of-concept or detection template is known for this vulnerability.
Advisories & patches
- Advisorywordfence.com
Related CVEs
More in Online Scheduling and Appointment Booking System – Bookly
All 32| Severity | Vulnerability | CVE | Published |
|---|---|---|---|
| High7.2 | Authenticated (Custom+) PHP Object Injection via 'value' Parameter ≤28.2Update to 28.3 | CVE-2026-12626 | |
| Medium6.8 | Insecure Direct Object Reference to Authenticated (Subscriber+) Privilege Escalation via 'id' and 'wp_user_id' Parameters via Query String / JSON Body ≤28.4Update to 28.5 | CVE-2026-104898 | |
| Medium5.3 | Unauthenticated Sensitive Information Exposure in 'phone' Parameter to bookly_render_details ≤28.4Update to 28.5 | CVE-2026-103365 | |
| Medium4.3 | Authenticated (Staff+) Insecure Direct Object Reference ≤28.2Update to 28.3 | CVE-2026-86839 | |
| Medium5.3 | Unauthenticated Payment Bypass ≤28.2Update to 28.3 | CVE-2026-86838 |
- High7.2Authenticated (Custom+) PHP Object Injection via 'value' Parameter
≤28.2Update to 28.3
- Medium6.8Insecure Direct Object Reference to Authenticated (Subscriber+) Privilege Escalation via 'id' and 'wp_user_id' Parameters via Query String / JSON Body
≤28.4Update to 28.5
- Medium5.3Unauthenticated Sensitive Information Exposure in 'phone' Parameter to bookly_render_details
≤28.4Update to 28.5
- Medium4.3Authenticated (Staff+) Insecure Direct Object Reference
≤28.2Update to 28.3
- Medium5.3Unauthenticated Payment Bypass
≤28.2Update to 28.3
Same weakness (Cross-Site Scripting)
All Cross-Site Scripting| Severity | Vulnerability | CVE | Published |
|---|---|---|---|
| High7.2 | Unauthenticated Stored Cross-Site Scripting via Comment User-Agent Header | CVE-2026-120688 | |
| Critical9.8 | Unauthenticated Arbitrary File Upload via File Upload via Public Form Submission | CVE-2026-125055 | |
| Critical9.8 | Unauthenticated PHP Object Injection to Remote Code Execution via 'form' Parameter | CVE-2026-119077 | |
| Medium5.3 | Unauthenticated Sensitive Information Exposure in 'search' Parameter | CVE-2026-121518 |
- High7.2Unauthenticated Stored Cross-Site Scripting via Comment User-Agent Header
EZ SQL Reports Shortcode Widget and DB Backup
≤5.25.25Update to 5.26.45
- Critical9.8Unauthenticated Arbitrary File Upload via File Upload via Public Form Submission
Chatterbug Forms – Fast, Flexible WordPress Form Builder
≤1.0.2Update to 1.1
- Critical9.8Unauthenticated PHP Object Injection to Remote Code Execution via 'form' Parameter
ELEX WordPress HelpDesk & Customer Ticketing System
≤3.3.9Update to 3.4.0
- Medium5.3Unauthenticated Sensitive Information Exposure in 'search' Parameter
Customer Reviews for WooCommerce
≤5.127.0Update to 5.128.0
Timeline
CVE published
Severity high, CVSS 7.2
Record last updated
Sources & licenses
Wordfence record- Vulnerability data
- Wordfence Intelligence. Copyright 2012-2026 Defiant Inc. Licensed under the CC BY-SA 4.0.
- CVE® identifiers
- Copyright 1999-2026 The MITRE Corporation. Used under the CVE Program. CVE® is a registered trademark of The MITRE Corporation.
- CVSS / CWE
- National Vulnerability Database (NVD), shown unmodified. This product uses the NVD API but is not endorsed or certified by the NVD.
- VulnCrest content
- Summary, remediation guidance and page layout © VulnCrest. Not sourced from NVD.