CVE-2026-110653

The Appointment Booking Plugin – LatePoint | Calendar & Scheduling for WordPress plugin for WordPress is vulnerable to Authentication Bypass via Race Condition in all versions up to, and including, 5.7.4. This is due to a non-atomic read-modify-write on the OTP verification attempts counter in the verifyOTP function: the counter is incremented using a stale in-memory value with no conditional WHERE attempts < 10 guard on the UPDATE and no SELECT ... FOR UPDATE row lock, creating a TOCTOU window that allows concurrent requests to bypass the 10-attempt lockout. This makes it possible for unauthenticated attackers — who know a target customer's registered email address or phone number — to fire concurrent requests to the auth verify otp endpoint, defeat the lockout cap, brute-force the 6-digit OTP code, and authenticate as the targeted LatePoint customer, gaining full access to their account, bookings, and personal data. The nonce check present on the endpoint (otp verify otp nonce) does not mitigate this issue, as the nonce is publicly emitted by the unauthenticated request otp and resend otp endpoints and is trivially obtainable by any unauthenticated attacker prior to launching the race.