# CVE-2026-3651: Missing authorization in Build App Online

> Unauthenticated attackers can modify the author of arbitrary posts in the Build App Online WordPress plugin due to missing authorization checks.

- **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:** 21 Mar 2026
- **Updated:** 8 Apr 2026
- **Also known as:** GHSA-xcmm-m27h-87pr

## What is CVE-2026-3651?

CVE-2026-3651 is a medium-severity missing authorization vulnerability in hakeemnala Build App Online, published on 21 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Build App Online plugin for WordPress is vulnerable to unauthorized access in all versions up to, and including, 1.0.23. This is due to the plugin registering the 'build-app-online-update-vendor-product' AJAX action via wp_ajax_nopriv_ without proper authentication checks, capability verification, or nonce validation in the update_vendor_product() function. The function accepts a user-supplied post ID from the request and calls wp_update_post() to modify the post_author field without validating whether the user has permission to modify the specified post. This makes it possible for unauthenticated attackers to modify the post_author of arbitrary posts to 0 (orphaning posts from their legitimate authors), or for authenticated attackers to claim ownership of any post by setting themselves as the author.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-3651?


## How do I fix CVE-2026-3651?

No fix has been published for CVE-2026-3651 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-3651 being exploited?

There is no known exploitation of CVE-2026-3651 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-3651 and fix it if it is affected.

What it is: CVE-2026-3651 is a medium-severity missing authorization vulnerability in hakeemnala Build App Online, published on 21 Mar 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-2026-3651 in the wild and no public exploit code.

Affected product: hakeemnala Build App Online. 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-2026-3651/ (Markdown: https://insights.sbomify.com/CVE-2026-3651/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-3651
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-3651
- OSV: https://osv.dev/vulnerability/CVE-2026-3651

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-3651/
Summaries are generated and may contain mistakes; the official description above is the record.