# CVE-2026-3640: STRABL <= 4.5 - Unauthenticated Arbitrary Webhook Creation via REST API Endpoint

> Unauthenticated attackers can create fraudulent orders, modify statuses, and create users via an unprotected REST API endpoint in the STRABL WordPress plugin.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 19 Jun 2026
- **Updated:** 22 Jun 2026
- **Also known as:** GHSA-v9cf-wxpg-292v

## What is CVE-2026-3640?

CVE-2026-3640 is a medium-severity missing authorization vulnerability in strablengineering STRABL – A checkout solution, published on 19 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The STRABL – A checkout solution plugin for WordPress is vulnerable to Missing Authentication in all versions up to and including 4.5. The plugin registers a REST API webhook endpoint at /wp-json/strabl/webhook/order with a permission_callback of __return_true, which allows all incoming requests without any authentication or authorization checks. No shared secret, signature validation, HMAC verification, or token-based authentication is implemented. This makes it possible for unauthenticated attackers to create fraudulent WooCommerce orders and mark them as completed by supplying paymentStatus=paid, manipulate existing order statuses by providing an externalOrderId, create new WordPress user accounts with the customer role, issue refunds on existing orders, cancel existing orders, and apply chargeback fees — all without making a legitimate payment or having any valid credentials.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-3640?


## How do I fix CVE-2026-3640?

No fix has been published for CVE-2026-3640 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-3640 being exploited?

There is no known exploitation of CVE-2026-3640 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-3640 and fix it if it is affected.

What it is: CVE-2026-3640 is a medium-severity missing authorization vulnerability in strablengineering STRABL – A checkout solution, published on 19 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-3640 in the wild and no public exploit code.

Affected product: strablengineering STRABL – A checkout solution. 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-2026-3640/ (Markdown: https://insights.sbomify.com/CVE-2026-3640/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-3640
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-3640
- OSV: https://osv.dev/vulnerability/CVE-2026-3640

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-3640/
Summaries are generated and may contain mistakes; the official description above is the record.