Medium severity · published Mar 7, 2025
CVE-2024-13431
Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin <= 1.6.8.3 - Reflected Cross-Site Scripting
6.1
CVSS
0.4%
EPSS
No
On KEV
Description
The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the accent_color and background parameter in all versions up to, and including, 1.6.8.3 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 31% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AB
Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin · croixhaug
through 1.6.8.3 · source: vendor
AB
Appointment Booking Calendar · Nsquared
before 1.6.8.5 · source: NVD
Affected product
AB
Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin
croixhaug
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2024-13431
CVE.org
https://www.cve.org/CVERecord?id=CVE-2024-13431
blog.lucianohanna.com.br
https://blog.lucianohanna.com.br/security/cve/cve-2024-13431-reflected-xss-no-simply-schedule-appointments/
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.8.3/booking-app-new/iframe-inner.php#L182
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.8.3/includes/class-styles.php#L116
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.8.3/includes/class-styles.php#L97
Patch
https://plugins.trac.wordpress.org/changeset/3246760/simply-schedule-appointments/trunk/booking-app-new/iframe-inner.php
Third Party Advisory
https://www.wordfence.com/threat-intel/vulnerabilities/id/f6e3e5dd-b9f1-4d24-98cc-b6ab319434e4?source=cve
More from Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin
7.5
CVE-2026-7797
Appointment Booking Calendar <= 1.6.11.8 - Unauthenticated SQL Injection via 'append_where_sql' Parameter
7.5
CVE-2026-3658
Appointment Booking Calendar <= 1.6.10.0 - Unauthenticated SQL Injection via 'fields' Parameter
7.5
CVE-2026-3045
Appointment Booking Calendar <= 1.6.9.29 - Missing Authorization to Unauthenticated Sensitive Information Exposure via Settings REST API Endpoint
7.5
CVE-2026-1708
Appointment Booking Calendar <= 1.6.9.27 - Unauthenticated SQL Injection via 'append_where_sql' Parameter
7.5
CVE-2025-12166
Simply Schedule Appointments <= 1.6.9.9 - Unauthenticated SQL Injection via `order` and `append_where_sql` Parameters