dbcve.org
Mfa MailTYPO3 extension · Mrsilaz

CVE-2026-4208

HIGH · 8.8 CVSS v3.1 Published 2026-03-17
Fix available
A fix is available. Upgrade to 1.0.7 or later.
See remediation →
94/100
Remediation priority · Urgent
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

The extension fails to properly reset or invalidate the generated MFA code after successful authentication. This creates a state where future login attempts can bypass MFA by simply providing an empty string as the MFA code to the extension's MFA provider, exploiting the failure to clear the session state.

MitigationImplement proper post-authentication state management by invalidating the MFA code after each successful login and enforcing validation that a non-empty, valid MFA code is provided before accepting authentication.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Mfa MailTYPO3 extension
Affected:< 1.0.7= 2.0.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify Mrsilaz Mfa Mail extension is installed
    Locate the extension in your CMS/plugin manager or check the installed extensions directory for 'mrsilaz-mfa-mail' or similar naming
    Affected if the extension is present in your environment
  2. Determine installed version of the extension
    Check the extension's version metadata through your CMS admin panel, composer.json, or extension manifest file
    Affected if version is less than 1.0.7 or equals 2.0.0 exactly
  3. Confirm MFA functionality is enabled
    Review the extension configuration settings to verify MFA/2FA authentication is active for user logins
    Affected if MFA is enabled and the extension is handling authentication flows
  4. Test empty MFA code behavior
    Attempt a login with MFA required, then after successful authentication, try a subsequent login using an empty string as the MFA code through the extension's MFA provider
    Affected if authentication succeeds with an empty MFA code on the second attempt, indicating the session state was not invalidated

You are affected if the Mrsilaz Mfa Mail extension is installed at a version less than 1.0.7 or exactly 2.0.0, MFA is enabled, and subsequent logins can succeed using an empty string as the MFA code.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 1.0.7 or later
Fixed in 1.0.7
Interim mitigation

Implement proper post-authentication state management by invalidating the MFA code after each successful login and enforcing validation that a non-empty, valid MFA code is provided before accepting authentication.

Recommended fix High confidence

mfa_mail version 1.0.7 or later (or a version > 2.0.0 if using the 2.x branch)

  1. 1. Backup your TYPO3 installation and database before making any changes.
  2. 2. Update the 'mfa_mail' extension to version 1.0.7 or later using Composer: `composer update typo3-ter/mfa-mail` or via the TYPO3 extension manager.
  3. 3. Clear all caches after the update: `typo3/cache/flush` or via the Install Tool.
  4. 4. Verify the MFA functionality works correctly by testing a login flow with MFA.
  5. 5. Ensure that after successful authentication, the MFA session is properly reset and cannot be bypassed with an empty string.
Caveat Review custom MFA configurations or extensions that may depend on the previous MFA behavior, as the fix changes how the MFA code is reset after authentication.

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Mfa Mail Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,930
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,088.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-4208 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data