CVE-2026-13358
Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin <= 1.6.12.10 - Authenticated (Contributor+) Insecure Direct Object Reference to Sensitive Information Exposure
Description
The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 1.6.12.10 via the ssa_past_appointments due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with contributor-level access and above, to access appointment records belonging to arbitrary users and harvest the per-appointment ownership tokens (32-character hashes) embedded in the rendered HTML, which can then be used without any authentication to read or modify those appointments including full customer PII such as name, email, phone number, and private notes. The /wp-json/ssa/v1/render-shortcode REST endpoint is registered unconditionally on rest_api_init regardless of whether the Divi theme is installed, and its permission callback only requires current_user_can('edit_posts'), meaning any Contributor-level account is sufficient to trigger this entire exploit chain.
INFO
Published Date :
Aug. 16, 2026, 5:16 a.m.
Last Modified :
Aug. 16, 2026, 5:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-13358
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update the Appointment Booking Calendar plugin immediately.
- Ensure the plugin is at least version 1.6.12.11.
- Verify access control for all user roles.
- Review plugin settings for security options.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-13358.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-13358 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-13358
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-13358 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-13358 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Aug. 16, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'croixhaug', 'product': 'Simply Schedule Appointments', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '1.6.12.10'}], 'defaultStatus': 'unaffected'}] Added Description The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 1.6.12.10 via the ssa_past_appointments due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with contributor-level access and above, to access appointment records belonging to arbitrary users and harvest the per-appointment ownership tokens (32-character hashes) embedded in the rendered HTML, which can then be used without any authentication to read or modify those appointments including full customer PII such as name, email, phone number, and private notes. The /wp-json/ssa/v1/render-shortcode REST endpoint is registered unconditionally on rest_api_init regardless of whether the Divi theme is installed, and its permission callback only requires current_user_can('edit_posts'), meaning any Contributor-level account is sufficient to trigger this entire exploit chain. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Added CWE CWE-639 Added Reference https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.11.0/includes/class-appointment-model.php#L1936 Added Reference https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.11.0/includes/class-db-model.php#L325 Added Reference https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.11.0/includes/class-divi.php#L237 Added Reference https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.11.0/includes/class-divi.php#L254 Added Reference https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.11.0/includes/class-shortcodes.php#L781 Added Reference https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.4/includes/class-appointment-model.php#L1936 Added Reference https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.4/includes/class-db-model.php#L325 Added Reference https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.4/includes/class-divi.php#L237 Added Reference https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.4/includes/class-divi.php#L254 Added Reference https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.4/includes/class-shortcodes.php#L781 Added Reference https://plugins.trac.wordpress.org/changeset?reponame=&old=3617759%40simply-schedule-appointments&new=3617759%40simply-schedule-appointments Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/5dbe5094-d255-46b1-9e8e-9c48cd74e8a2?source=cve