CVE-2026-18315 - Appointment Booking And Scheduler System Plugin
CVE-2026-18315
The TrueBooker – Appointment Booking and Scheduler System plugin for WordPress is vulnerable to Authorization Bypass Through User-Controlled Key leading to Account Takeover in all versions up to, and including, 1.2.6. This is due to the admin_user_create_cus AJAX handler lacking any authentication or capability check before passing the attacker-supplied truebooker_wp_user_id parameter directly to wp_update_user. This makes it possible for unauthenticated attackers to overwrite the email address of any WordPress user — including an administrator — and then complete the standard WordPress lost-password flow to fully take over the targeted account.
CVE-2026-18315
CRITICAL
CVSS 9.8
Published 2026-08-19
Updated 2026-08-20
AI Risk Critical (100/100)
Active Exploit: No strong signal
Published Exploit: No public exploit references
Priority: P1 Immediate
Severity Band
CRITICAL
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected Components
3
Reference Links
5
AI Risk Engine
Critical (100/100)
Exploitability
Very High
Active Exploitation
No strong signal
Published Exploit Status
No public exploit references
AI Context
Machine-generated threat intelligence
AI
Updated 9 hours ago
AI enriched 9 hours ago (2026-08-21 20:38 UTC)
Technical Summary
The TrueBooker – Appointment Booking and Scheduler System plugin for WordPress is vulnerable to Authorization Bypass Through User-Controlled Key leading to Account Takeover in all versions up to, and including, 1.2.6. This is due to the admin_user_create_cus AJAX handler lacking any authentication or capability check before passing the attacker-supplied truebooker_wp_user_id parameter directly to wp_update_user. This makes it possible for unauthenticated attackers to overwrite the email address of any WordPress user — including an administrator — and then complete the standard…
Potential Impact
Severity is CRITICAL (CVSS 9.8). Depending on deployment context, affected components may be exposed to unauthorized actions or data integrity risk.
Exploitability Assessment
Exploitability is assessed as Very High based on remote code execution potential, low-bar exploit prerequisites.
Primary risk drivers: remote code execution potential, low-bar exploit prerequisites
Mitigation Recommendations
Validate affected product versions, prioritize patching, and monitor references for vendor remediation guidance. If immediate patching is not possible, apply compensating controls and limit exposure of vulnerable surfaces.
Detection & Monitoring
Track authentication anomalies, unexpected file writes, and suspicious plugin API activity around affected components.
Business Impact Lens
AI risk score 100/100 (Critical, Very High) with priority P1 Immediate. Prioritize remediation where affected components process customer data, admin sessions, or Internet-exposed workflows.