# CVE-2026-17538: Missing authorization in Appointment Booking Plugin – LatePoint | Calendar & Scheduling for WordPress

> Authenticated attackers can modify arbitrary customer PII and potentially take over accounts via email overwrite due to missing ownership checks.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 7 Oct 2026
- **Updated:** 10 Oct 2026
- **Also known as:** GHSA-gw8m-rqgv-6j3j

## What is CVE-2026-17538?

CVE-2026-17538 is a medium-severity missing authorization vulnerability in Appointment Booking Plugin – LatePoint | Calendar & Scheduling for WordPress, published on 7 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

The LatePoint - Appointment Booking & Reservation plugin for WordPress is vulnerable to Insecure Direct Object Reference in versions up to, and including, 5.6.9. This is due to the process_step_customer() function using is_user_logged_in() as the sole gate before merging POSTed customer data into an existing LatePoint customer, without any ownership checks. This makes it possible for authenticated attackers, with Subscriber-level access and above, to modify the personal information (first name, last name, email, phone, notes) of arbitrary LatePoint customers, and, when the contact_merge setting is 'phone', to overwrite the victim's email address and take over the account via a password reset.

Weakness: CWE-639 (Authorization Bypass Through User-Controlled Key)

## Which versions are affected by CVE-2026-17538?


## How do I fix CVE-2026-17538?

No fix has been published for CVE-2026-17538 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-17538 being exploited?

There is no known exploitation of CVE-2026-17538 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-17538 and fix it if it is affected.

What it is: CVE-2026-17538 is a medium-severity missing authorization vulnerability in Appointment Booking Plugin – LatePoint | Calendar & Scheduling for WordPress, published on 7 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-17538 in the wild and no public exploit code.

Affected product: Appointment Booking Plugin – LatePoint | Calendar & Scheduling for WordPress. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-17538/ (Markdown: https://insights.sbomify.com/CVE-2026-17538/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-17538
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-17538
- OSV: https://osv.dev/vulnerability/CVE-2026-17538

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-17538/
Summaries are generated and may contain mistakes; the official description above is the record.