Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin <= 1.6.12.10 — Authenticated (Contributor+) Insecure Direct Object Reference to Sensitive Information Exposure
CVE-2026-13358Published · Updated Action summary
Affected: ≤1.6.12.10Update to 1.6.12.11 or newer
All remediation steps- Severity
- Medium6.5
- CVSS
- 6.5CVSS 3.1 · CNA (Wordfence)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:NWhat does this vector mean?
AV:NAttack vector- Network
AC:LAttack complexity- Low
PR:LPrivileges required- Low
UI:NUser interaction- None
S:UScope- Unchanged
C:HConfidentiality- High
I:NIntegrity- None
A:NAvailability- None
- Required access
- Unknown
- Exploit prediction (EPSS)
- No score
- CISA KEV
- Not listed
On this page8
Am I affected?
Simply Schedule Appointments simply-schedule-appointments
- Affected≤ 1.6.12.10
- Patched in1.6.12.11
Update to 1.6.12.11 or newer.
You are affected if you run ≤ 1.6.12.10. Version 1.6.12.11 and later are not affected by this issue.
- Check your version: in wp-admin go to Plugins → Installed Plugins and read the version under Simply Schedule Appointments.
- No admin access? Run a passive check of your site. It reads public files only.
What to do
- Update to version 1.6.12.11, or a newer patched version
- Rotate administrator passwords and application secrets if the site ran a vulnerable version while publicly reachable.
- Watch Simply Schedule Appointments to get an email when the next vulnerability is published.
Advisory
Source description from Wordfence Intelligence, credited to Michael Iden (Mickhat).
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.
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 Simply Schedule Appointments
All 52| Severity | Vulnerability | CVE | Published |
|---|---|---|---|
| Medium5.3 | Missing Authorization ≤1.6.13.0Update to 1.6.13.4 | CVE-2026-125437 | |
| High7.2 | Unauthenticated Stored Cross-Site Scripting ≤1.6.12.35Update to 1.6.12.37 | CVE-2026-110382 | |
| Medium4.3 | Authenticated (Contributor+) Insecure Direct Object Reference ≤1.6.12.35Update to 1.6.12.37 | CVE-2026-110381 | |
| High7.2 | Unauthenticated Stored Cross-Site Scripting via 'status' Parameter via /wp-json/ssa/v1/appointments/{id} ≤1.6.12.35Update to 1.6.12.37 | CVE-2026-104000 | |
| Medium5.3 | Incorrect Authorization to Unauthenticated Sensitive Field Modification via Appointment Public Token ≤1.6.11.11Update to 1.6.12.0 | CVE-2026-6723 |
- Medium5.3Missing Authorization
≤1.6.13.0Update to 1.6.13.4
- High7.2Unauthenticated Stored Cross-Site Scripting
≤1.6.12.35Update to 1.6.12.37
- Medium4.3Authenticated (Contributor+) Insecure Direct Object Reference
≤1.6.12.35Update to 1.6.12.37
- High7.2Unauthenticated Stored Cross-Site Scripting via 'status' Parameter via /wp-json/ssa/v1/appointments/{id}
≤1.6.12.35Update to 1.6.12.37
- Medium5.3Incorrect Authorization to Unauthenticated Sensitive Field Modification via Appointment Public Token
≤1.6.11.11Update to 1.6.12.0
Timeline
CVE published
Severity medium, CVSS 6.5
Record last updated
Sources & licenses
Wordfence record- Vulnerability data
- Wordfence Intelligence. [object Object] Licensed under the CC BY-SA 4.0.
- CVE® identifiers
- [object Object]. 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.