CVE-2026-110653
Appointment Booking Plugin <= 5.7.4 - Unauthenticated Authentication Bypass via Race Condition on OTP Attempts Counter
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
9.1
Appointment Booking Plugin <= 5.7.4 - Unauthenticated Authentication Bypass via Race Condition on OTP Attempts Counter
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.
- Record
CVE-2026-110653- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-287
- Updated
- 2026-11-02
EUVDEUVD-2026-103217
9.1
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.
- Record
EUVD-2026-103217- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-3xwr-ghgc-2994
9.1
The Appointment Booking Plugin – LatePoint | Calendar & Scheduling for WordPress plugin for...
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.
- Record
GHSA-3xwr-ghgc-2994- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-287
- Updated
- 2026-11-02
NVD
9.1
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.
- Record
CVE-2026-110653- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-287
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-110653 is a critical vulnerability (CVSS 9.1) in Latepoint Appointment Booking Plugin – Latepoint | Calendar & Scheduling For Wordpress, published October 17, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.40%, the 34th percentile. No source names a fixed version.
References
wordfence.com/threat-intel/vulnerabilities/id/61fbc1dd-06c9-409b-8cad-3f350b38dfc3?source=cve
plugins.trac.wordpress.org/browser/latepoint/tags/5.7.4/lib/helpers/otp_helper.php
plugins.trac.wordpress.org/browser/latepoint/tags/5.7.4/lib/controllers/auth_controller.php
plugins.trac.wordpress.org/browser/latepoint/tags/5.7.4/lib/models/model.php
plugins.trac.wordpress.org/browser/latepoint/tags/5.7.5/lib/helpers/otp_helper.php
nvd.nist.gov/vuln/detail/CVE-2026-110653
github.com/advisories/GHSA-3xwr-ghgc-2994