# CVE-2026-4208: Authentication Bypass in extension "E-Mail MFA Provider" (mfa_email)

> Attackers can bypass Multi-Factor Authentication by submitting an empty code, allowing unauthorized access to TYPO3 accounts.

- **Severity:** High 7.7 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Mar 2026
- **Updated:** 24 Mar 2026
- **Also known as:** GHSA-29r8-gvx4-r9w3

## What is CVE-2026-4208?

CVE-2026-4208 is a high-severity authentication bypass vulnerability in TYPO3 Extension "E-Mail MFA Provider", published on 17 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

The extension fails to properly reset the generated MFA code after successful authentication. This leads to a possible MFA bypass for future login attempts by providing an empty string as MFA code to the extensions MFA provider.

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

## Which versions are affected by CVE-2026-4208?

4 open source packages ship an affected version, including ralffreit/mfa-email. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `ralffreit/mfa-email` | Packagist | All versions | 1.0.7 |
| `ralffreit/mfa-email` | Packagist | All versions | 1.0.7 |
| `ralffreit/mfa-email` | Packagist | From 2.0.0 | 2.0.1 |
| `ralffreit/mfa-email` | Packagist | From 2.0.0 | 2.0.1 |

Products: Mrsilaz Mfa Mail.

## How do I fix CVE-2026-4208?

Upgrade ralffreit/mfa-email to a fixed version for your release line: 1.0.7 or 2.0.1.

## Is CVE-2026-4208 being exploited?

There is no known exploitation of CVE-2026-4208 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-4208 and fix it if it is affected.

What it is: CVE-2026-4208 is a high-severity authentication bypass vulnerability in TYPO3 Extension "E-Mail MFA Provider", published on 17 Mar 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-2026-4208 in the wild and no public exploit code.

Affected packages and fixed versions:
- ralffreit/mfa-email (Packagist): affected all versions; fixed in 1.0.7
- ralffreit/mfa-email (Packagist): affected all versions; fixed in 1.0.7
- ralffreit/mfa-email (Packagist): affected from 2.0.0; fixed in 2.0.1
- ralffreit/mfa-email (Packagist): affected from 2.0.0; fixed in 2.0.1

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-2026-4208/ (Markdown: https://insights.sbomify.com/CVE-2026-4208/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-4208
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-4208
- OSV: https://osv.dev/vulnerability/CVE-2026-4208

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-4208/
Summaries are generated and may contain mistakes; the official description above is the record.