CVE-2026-13358 Information disclosure in Simply Schedule Appointments
Authenticated contributors can access arbitrary appointment records and tokens, enabling unauthorized reading and modification of customer PII.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-13358?
CVE-2026-13358 is a medium-severity vulnerability in croixhaug Simply Schedule Appointments, published on 16 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-639
Which versions are affected by CVE-2026-13358?
How do I fix CVE-2026-13358?
No fix has been published for CVE-2026-13358 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-13358 being exploited?
There is no known exploitation of CVE-2026-13358 in the wild and no public exploit code.
Sources
Also known as GHSA-w9gm-5x7r-8v42.