CVE-2026-77705 in Booking for Appointments and Events Calendar Plugin
Summary
by MITRE • 09/12/2026
The Booking for Appointments and Events Calendar WordPress plugin before 2.4.10 does not verify that the user editing a customer or employee record is entitled to modify the WordPress account linked to it, allowing users holding Amelia's customer or employee management permissions to set the password and email address of other users' WordPress accounts and take them over.
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Analysis
by VulDB Data Team • 09/12/2026
The vulnerability identified in the Booking for Appointments and Events Calendar plugin, specifically versions prior to 2.4.10, represents a critical failure in access control mechanisms within the application's user management subsystem. This flaw allows authenticated users with specific roles, such as customers or employees managed by the Amelia module, to perform unauthorized administrative actions on WordPress accounts associated with other entities. The core technical deficiency lies in the absence of proper authorization checks when processing requests that modify customer or employee records. Specifically, the plugin fails to verify whether the initiating user has the requisite privileges to alter the linked WordPress account details, such as email addresses and passwords, for any given record rather than only their own. This lack of server-side validation enables an attacker with relatively low-level permissions to escalate their influence significantly by targeting other users' accounts within the system.
From a technical perspective, this issue is classified under CWE-269, which denotes Improper Privilege Control. The vulnerability arises because the application logic assumes that any user interacting with the customer or employee management interface has implicit authority over all records visible to them, rather than restricting modifications based on ownership or explicit administrative rights. When a request is submitted to update an account's credentials, the backend processes this change without confirming if the requester owns the target WordPress ID linked in the database. This oversight allows for direct manipulation of authentication data, effectively bypassing standard role-based access controls that are fundamental to secure web application architecture. The flaw exploits the trust placed in user input regarding which record is being edited, leading to a complete breakdown of identity verification during credential updates.
The operational impact of this vulnerability is severe, as it facilitates account takeover scenarios for any WordPress users whose accounts are linked through the plugin's data model. An attacker can reset the password and change the email address associated with an administrator or another privileged user, thereby gaining full control over that individual's WordPress session. This compromise extends beyond mere access to sensitive information; it allows the adversary to manipulate site content, install malicious plugins, exfiltrate database contents, or use the compromised account as a pivot point for further attacks against the broader infrastructure. The ability to impersonate other users undermines the integrity of user-specific data and can lead to significant reputational damage and loss of trust among clients who rely on the appointment booking services provided by the vulnerable application.
This vulnerability aligns with several techniques described in the MITRE ATT&CK framework, particularly T1078 Valid Accounts, which covers the use of legitimate credentials obtained through various means to gain access. In this context, while the attacker may not have stolen existing passwords initially, they are effectively creating valid accounts for themselves by hijacking others' identities. It also relates to T1531 Account Access Removal, as changing email addresses and passwords can lock out original owners from their own accounts. The exploitation path typically involves identifying a target user's record within the customer or employee list, submitting a crafted request with modified credential fields, and thereby assuming control of that account without needing prior knowledge of its password.
Mitigation strategies must prioritize immediate patching to version 2.4.10 or later, where these authorization checks have been implemented by the developers. Until an update is applied, administrators should restrict access to the customer and employee management interfaces to only those users with explicit administrative privileges, thereby limiting exposure to individuals who might attempt such exploits. Additionally, implementing strict input validation on the server side for all user modification endpoints ensures that ownership verification occurs before any changes are committed to the database. Regular security audits focusing on role-based access control logic across all plugin modules can help identify similar flaws in other areas of the application. Monitoring logs for unusual password reset activities or email address changes associated with non-administrative users can also provide early detection indicators for potential exploitation attempts.