CVE-2026-27836
Unauthenticated Account Creation in phpMyFAQ WebAuthn Endpoint
Publication date: 2026-02-27
Last updated on: 2026-03-04
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| phpmyfaq | phpmyfaq | to 4.0.18 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-862 | The product does not perform an authorization check when an actor attempts to access a resource or perform an action. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
The vulnerability exists in phpMyFAQ versions prior to 4.0.18 in the WebAuthn prepare endpoint (/api/webauthn/prepare). This endpoint allows the creation of new active user accounts without requiring any authentication, CSRF protection, captcha, or configuration checks.
As a result, unauthenticated attackers can create unlimited user accounts even if the registration feature is disabled.
This issue was fixed in version 4.0.18.
How can this vulnerability impact me? :
This vulnerability allows attackers to create unlimited active user accounts without any restrictions or authentication.
Such unauthorized account creation can lead to abuse of the system, potential denial of service by exhausting resources, and possible misuse of privileges associated with user accounts.
The CVSS score indicates a high impact on integrity (I:H), meaning attackers can manipulate or inject unauthorized data or actions through these accounts.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should upgrade phpMyFAQ to version 4.0.18 or later, where the issue has been fixed.
Until the upgrade is applied, consider restricting access to the /api/webauthn/prepare endpoint to trusted users or networks to prevent unauthenticated account creation.