CVE-2025-13317: The Appointment Booking Calendar plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 1.3.96. This is due...

Description

The Appointment Booking Calendar plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 1.3.96. This is due to the plugin exposing an unauthenticated booking processing endpoint (cpabc_appointments_check_IPN_verification) that trusts attacker-supplied payment notifications without verifying their origin, authenticity, or requiring proper authorization checks. This makes it possible for unauthenticated attackers to arbitrarily confirm bookings and insert them into the live calendar via the 'cpabc_ipncheck' parameter, triggering administrative and customer notification emails and disrupting operations.

Metrics

CVSS 3.1

5.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

EPSS Probability

0.24%

15.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-862

References

Timeline

Published: Nov 22, 2025
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2025-13317?

The Appointment Booking Calendar plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 1.3.96. This is due to the plugin exposing an unauthenticated booking processing endpoint (cpabc_appointments_check_IPN_verification) that trusts attacker-supplied payment notifications without verifying their origin, authenticity, or requiring proper authorization checks. This makes it possible for unauthenticated attackers to arbitrarily confirm bookings and insert them into the live calendar via the 'cpabc_ipncheck' parameter, triggering administrative and customer notification emails and disrupting operations.

How severe is CVE-2025-13317?

CVE-2025-13317 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 0.24% probability of exploitation in the next 30 days.

How do I fix CVE-2025-13317?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.