CVE-2026-89294
HighCVSS 7.5Summary
The Simply Schedule Appointments plugin for WordPress is vulnerable to Local File Inclusion in all versions up to, and including, 1.6.12.27 via the 'ssa_locale' parameter. This makes it possible for authenticated attackers, with subscriber-level access and above, to include and execute arbitrary .php files on the server, allowing the execution of any PHP code in those files. This can be used to bypass access controls, obtain sensitive data, or achieve code execution in cases where .php file types can be uploaded and included. Notably, exploitation does not require authentication in practice, as the locale filter is installed unconditionally on every request during plugins_loaded and the callback performs no nonce or capability check before returning the raw GET parameter value.
Risk Assessment
Risk of access control bypass, sensitive data exposure, or code execution on the server, even without authentication.
Recommendation
Update the plugin to the latest version immediately and restrict the ability to upload .php files on the server.
Other vulnerabilities in Simply Schedule Appointments
See all- CVE-2026-94673Medium
Unauthenticated Insecure Direct Object References (IDOR) vulnerability in Simply Schedule Appointments up to version 1.6.12.31.
- CVE-2026-94074Medium
Simply Schedule Appointments plugin version 1.6.12.29 and earlier contains a Broken Access Control vulnerability that can be exploited without authentication, allowing unauthorized access to functionality.
- CVE-2026-65508Critical
Unauthenticated SQL Injection vulnerability in Simply Schedule Appointments versions up to 1.6.12.10.
- CVE-2026-39493Critical
There is an unauthenticated SQL injection vulnerability in Simply Schedule Appointments versions up to 1.6.9.27.
- CVE-2026-92245High
The Simply Schedule Appointments plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 1.6.12.32 via the 'recursive' parameter. Unauthenticated attackers can extract customer PII (names, email addresses, phone numbers, custom form field data) and per-appointment public_token values, which also enables deletion of arbitrary appointments via the DELETE /wp-json/ssa/v1/appointments/{id} endpoint.
- CVE-2026-91109Medium
The Simply Schedule Appointments plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to and including 1.6.12.31 via the 'complete_group' parameter due to missing validation on a user-controlled key. This allows authenticated attackers with subscriber-level access and above to disclose every co-booker's private id_token and PII, then use each leaked token to read, overwrite arbitrary appointment meta, or cancel the co-booker's appointment.
- CVE-2026-84764High
Unauthenticated CSRF vulnerability in Simply Schedule Appointments versions up to 1.6.12.23. An attacker can exploit this to perform unauthorized actions in the context of a logged-in administrator.
- CVE-2026-65513High
Unauthenticated Cross Site Scripting (XSS) vulnerability in Simply Schedule Appointments plugin up to version 1.6.12.10. An unauthenticated attacker can inject malicious scripts.
- CVE-2026-15254Medium
The Simply Schedule Appointments WordPress plugin before version 1.6.12.11 does not perform a capability check on an administrative appointment-listing shortcode, and its per-user result scoping fails open for non-staff users. This allows users with the Contributor role and above to disclose all customers' appointment records, including names, email addresses, phone numbers and notes, across the whole site.
- CVE-2026-16540High
The Simply Schedule Appointments WordPress plugin before version 1.6.12.6 does not restrict a bulk appointment operation to the requester's own records. Unauthenticated users can retrieve personal data of all appointments and, on premium editions, permanently delete them.
Original NVD description (English source)
The Simply Schedule Appointments plugin for WordPress is vulnerable to Local File Inclusion in all versions up to, and including, 1.6.12.27 via the 'ssa_locale' parameter parameter. This makes it possible for authenticated attackers, with subscriber-level access and above, to include and execute arbitrary .php files on the server, allowing the execution of any PHP code in those files. This can be used to bypass access controls, obtain sensitive data, or achieve code execution in cases where .php file types can be uploaded and included. Notably, exploitation does not require authentication in practice, as the locale filter is installed unconditionally on every request during plugins_loaded and the callback performs no nonce or capability check before returning the raw GET parameter value.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS