# CVE-2023-2027: ZM Ajax Login & Register <= 2.0.2 - Authentication Bypass

> Unauthenticated attackers can bypass authentication and log in as any existing user, including administrators, via the Facebook login feature.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Apr 2023
- **Updated:** 8 Apr 2026
- **Also known as:** GHSA-x4hx-qqp4-qp78

## What is CVE-2023-2027?

CVE-2023-2027 is a critical authentication bypass vulnerability in zanematthew ZM Ajax Login & Register, published on 15 Apr 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The ZM Ajax Login & Register plugin for WordPress is vulnerable to authentication bypass in versions up to, and including, 2.0.2. This is due to insufficient verification on the user being supplied during a Facebook login through the plugin. This makes it possible for unauthenticated attackers to log in as any existing user on the site, such as an administrator, if they have access to the username.

Weakness: CWE-287 (Improper Authentication), CWE-288 (Authentication Bypass Using an Alternate Path or Channel)

## Which versions are affected by CVE-2023-2027?

It affects 1 product.


Products: Zm Ajax Login \& Register Project Zm Ajax Login \& Register.

## How do I fix CVE-2023-2027?

No fix has been published for CVE-2023-2027 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-2027 being exploited?

There is no known exploitation of CVE-2023-2027 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-2027 and fix it if it is affected.

What it is: CVE-2023-2027 is a critical authentication bypass vulnerability in zanematthew ZM Ajax Login & Register, published on 15 Apr 2023. 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-2023-2027 in the wild and no public exploit code.

Affected product: zanematthew ZM Ajax Login & Register. 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-2023-2027/ (Markdown: https://insights.sbomify.com/CVE-2023-2027/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-2027
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-2027
- OSV: https://osv.dev/vulnerability/CVE-2023-2027

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-2027/
Summaries are generated and may contain mistakes; the official description above is the record.