CVE-2024-2844 in Easy Appointments Plugin
Summary
by MITRE • 03/29/2024
The Easy Appointments plugin for WordPress is vulnerable to unauthorized modification of data due to insufficient user validation on the ajax_cancel_appointment() function in all versions up to, and including, 3.11.18. This makes it possible for unauthenticated attackers to cancel other users orders.
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Analysis
by VulDB Data Team • 04/14/2026
The vulnerability identified in CVE-2024-2844 affects the Easy Appointments plugin for WordPress, specifically targeting the ajax_cancel_appointment() function that lacks proper user authentication and authorization checks. This represents a critical security flaw that allows unauthenticated attackers to manipulate appointment data within the system, potentially compromising the integrity of scheduling operations across multiple user accounts. The issue exists in all versions up to and including 3.11.18, making it a widespread concern for WordPress administrators who have implemented this plugin for their appointment booking systems. The vulnerability directly violates fundamental security principles by permitting arbitrary data modification without proper verification of user credentials or privileges.
From a technical perspective, the flaw stems from insufficient input validation and authentication mechanisms within the plugin's ajax_cancel_appointment() function. The function fails to verify whether the requesting user has legitimate authorization to cancel a specific appointment, allowing any remote attacker to submit malicious requests that manipulate appointment status. This type of vulnerability aligns with CWE-863, which describes "Incorrect Authorization" where an attacker can perform actions they should not be permitted to execute due to inadequate access control validation. The absence of proper session management and user identity verification creates an exploitable path where attackers can craft requests that appear to originate from legitimate users, bypassing the plugin's intended security controls.
The operational impact of this vulnerability extends beyond simple data manipulation, as it can lead to significant service disruption and potential financial losses for businesses relying on the Easy Appointments plugin. Attackers can cancel appointments for other users, potentially causing scheduling conflicts, loss of revenue, and damage to customer relationships. The unauthenticated nature of the attack means that no prior access or credentials are required to exploit this vulnerability, making it particularly dangerous in environments where the plugin is widely used. This weakness can be leveraged as part of broader attack campaigns targeting WordPress installations, potentially serving as an initial foothold for more extensive system compromise. The vulnerability also impacts the principle of least privilege, as it allows unauthorized modification of data that should only be accessible to authenticated users with appropriate permissions.
Security mitigations for this vulnerability should prioritize immediate patching of the Easy Appointments plugin to the latest version where the authorization checks have been properly implemented. Administrators should also implement additional security measures such as monitoring for unusual appointment cancellation patterns, restricting access to the plugin's ajax endpoints through web application firewalls, and ensuring that proper authentication mechanisms are in place for all user interactions. Network-level controls can help detect and block malicious requests attempting to exploit this vulnerability, while regular security audits should verify that similar authorization flaws do not exist in other plugin components. This vulnerability demonstrates the importance of implementing robust access control mechanisms and proper input validation as outlined in the OWASP Top Ten security principles, particularly focusing on authentication and authorization controls that align with the MITRE ATT&CK framework's privilege escalation and defense evasion techniques.