CVE-2026-7493
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk28th percentile - higher than 28% of all known CVEs
Summary
The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin for WordPress up to version 1.6.11.5 is vulnerable to DoS. A publicly accessible REST API endpoint (/wp-json/ssa/v1/async) calls PHP's sleep() with a user-supplied delay parameter without rate limiting, allowing unauthenticated attackers to exhaust PHP worker processes.
Risk Assessment
Risk of complete denial of service (DoS) for the WordPress site, preventing legitimate users from accessing it.
Recommendation
Update the Simply Schedule Appointments plugin to the latest version. Temporarily block access to the /wp-json/ssa/v1/async endpoint for unauthenticated users.
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-2026-89294High
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.
- 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-2026-110382High
The Simply Schedule Appointments plugin (up to version 1.6.12.35) is vulnerable to stored XSS due to improper neutralization of input during web page generation. An attacker can inject a malicious script that gets stored and executed.
- CVE-2026-104000High
The Simply Schedule Appointments plugin for WordPress (versions up to and including 1.6.12.35) is vulnerable to stored Cross-Site Scripting via the 'status' parameter due to insufficient input sanitization and output escaping. An unauthenticated attacker can inject arbitrary web scripts into pages that execute when a user accesses the injected page.
- CVE-2026-110381Medium
The Simply Schedule Appointments plugin by NSquared contains an Authorization Bypass Through User-Controlled Key vulnerability that allows exploiting incorrectly configured access control security levels. This issue affects Simply Schedule Appointments from n/a through 1.6.12.35.
- 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.
Original NVD description (English source)
The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to denial of service in all versions up to, and including, 1.6.11.5. This is due to a publicly accessible REST API endpoint (/wp-json/ssa/v1/async) that calls PHP's sleep() function on a user-supplied delay parameter without any rate limiting. This makes it possible for unauthenticated attackers to exhaust PHP worker processes, denying access to the site to legitimate users.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

