LatePoint Appointment Booking Plugin up to 5.7.4 on WordPress verifyOTP toctou

Summaryinfo

A vulnerability, which was classified as critical, was found in LatePoint Appointment Booking Plugin up to 5.7.4. Affected by this vulnerability is the function verifyOTP. The manipulation results in toctou. This vulnerability is reported as CVE-2026-110653. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability classified as critical has been found in LatePoint Appointment Booking Plugin up to 5.7.4. Affected is the function verifyOTP. The manipulation with an unknown input leads to a toctou vulnerability. CWE is classifying the issue as CWE-367. The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at wordfence.com. This vulnerability is traded as CVE-2026-110653 since 10/14/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are known, but there is no available exploit.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Type

• WordPress Plugin

Vendor

• LatePoint

Name

• Appointment Booking Plugin

Version

• 5.7.0
• 5.7.1
• 5.7.2
• 5.7.3
• 5.7.4

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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