CVE-2026-65508 in Simply Schedule Appointments Plugin
Summary
by MITRE • 08/06/2026
Unauthenticated SQL Injection in Simply Schedule Appointments <= 1.6.12.10 versions.
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Analysis
by VulDB Data Team • 08/06/2026
Simply Schedule Appointments is a popular WordPress plugin designed to facilitate appointment booking and management for businesses. This plugin allows users to create appointment forms, manage schedules, and handle bookings through a user-friendly interface within the WordPress ecosystem. The vulnerability affects versions up to and including 1.6.12.10, making a significant number of installations potentially susceptible to exploitation. The plugin's functionality relies heavily on database interactions to store and retrieve appointment data, making it a prime target for SQL injection attacks that could compromise the entire WordPress installation.
The technical flaw manifests through improper input validation and sanitization within the plugin's database query execution processes. Specifically, the vulnerability occurs when user-supplied parameters are directly incorporated into SQL queries without adequate escaping or parameterization. Attackers can manipulate the plugin's administrative interfaces or frontend forms to inject malicious SQL commands that bypass authentication mechanisms. The vulnerability is classified as unauthenticated, meaning that no valid credentials are required to exploit it, significantly expanding the attack surface and making exploitation more accessible to threat actors with minimal privileges.
The operational impact of this vulnerability extends beyond simple data theft or modification. An attacker could potentially gain complete control over the WordPress installation by exploiting the SQL injection to execute arbitrary database commands. This could result in unauthorized access to sensitive customer information, appointment data, user credentials stored within the WordPress database, and potentially even administrative access to the entire website. The attack vector typically involves manipulating URL parameters or form inputs that are processed by the plugin's backend functions, allowing attackers to manipulate the underlying database queries through crafted malicious input.
The vulnerability aligns with CWE-89 which specifically addresses SQL injection flaws in software applications. This weakness is particularly dangerous because it enables attackers to perform unauthorized database operations including data retrieval, modification, or deletion. From an adversarial perspective, this vulnerability maps to several ATT&CK techniques including T1071.004 for application layer protocol manipulation and T1566 for phishing with social engineering elements that could be used to deliver malicious payloads. The attack chain typically involves reconnaissance to identify vulnerable installations followed by exploitation of the SQL injection to gain unauthorized access and potentially escalate privileges within the WordPress environment.
Mitigation strategies should begin with immediate patching of the affected plugin versions to the latest stable release that contains security fixes. System administrators should implement proper input validation and parameterized queries throughout the application code to prevent similar vulnerabilities in future development cycles. Network-level protections such as web application firewalls can provide additional defense-in-depth measures by monitoring for suspicious database query patterns. Regular security auditing of WordPress plugins and themes should be conducted to identify potentially vulnerable components, while maintaining up-to-date backups ensures rapid recovery in case of successful exploitation attempts. Additionally, implementing principle of least privilege access controls and regular security monitoring can help detect unauthorized database access attempts that might indicate exploitation of this vulnerability.