CVE-2026-110653: Improper Authentication Flaw in Appointment Booking Plugin – LatePoint | Calendar & Scheduli Scores 9.1 on CVSS
A newly published critical vulnerability in Appointment Booking Plugin – LatePoint | Calendar & Scheduli carries a CVSS score of 9.1. Here is what is affected and how to respond.
Key points
- CVE-2026-110653 affects Appointment Booking Plugin – LatePoint | Calendar & Scheduli.
- CVSS 9.1 (Critical).
- No exploitation confirmed yet.
Appointment Booking Plugin – LatePoint | Calendar & Scheduli is affected by CVE-2026-110653, a improper authentication that the National Vulnerability Database rates 9.1 out of 10.
At a glance
- CVE
- CVE-2026-110653
- Product
- Appointment Booking Plugin – LatePoint | Calendar & Scheduli
- CVSS
- 9.1 Critical
- Weakness
- improper authentication
- Exploited
- No known exploitation
What is the vulnerability?
The NVD entry states: 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 t
Affected versions
| Vendor | Product | Versions |
|---|---|---|
| Latepoint | Appointment Booking Plugin – LatePoint | Calendar & Scheduling for WordPress | up to 5.7.4 |
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
Is it being exploited?
There is no public confirmation of exploitation at the time of publication. It does not appear in CISA's Known Exploited Vulnerabilities catalog. We will update this report if that changes.
What should you do?
- Identify whether the affected product and versions run in your environment.
- Apply the vendor update listed in the advisory as soon as it is available.
- Limit network exposure of the affected service until it is patched.
- Monitor the vendor advisory for updated guidance or exploitation reports.
What to do and how to stay safe: CVE-2026-110653
- Vulnerability severity scores ignore your specific architecture and context.
- Exploitability depends on network exposure and user behavior, not just code flaws.
- Prioritization requires continuous asset inventory and threat intelligence alignment.
Risk-based vulnerability management focuses your limited resources on the flaws that actually threaten your business. Start by mapping your critical assets and checking for active exploits to prioritize your backlog.
Step-by-step guide: Risk-Based Vulnerability Management: Prioritize Fixes by Actual Danger
General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is CVE-2026-110653?
CVE-2026-110653 is a improper authentication vulnerability in Appointment Booking Plugin – LatePoint | Calendar & Scheduli.
How severe is CVE-2026-110653?
It has a CVSS score of 9.1 Critical.
Is CVE-2026-110653 being exploited?
There is no public confirmation of exploitation at the time of publication.
