How severe is CVE-2026-27836?

CVE-2026-27836 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2026-27836 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-27836?

CVE-2026-27836 affects Phpmyfaq. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-27836?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-27836 have an EU (EUVD) identifier?

Yes. CVE-2026-27836 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-9059.

When was CVE-2026-27836 published?

CVE-2026-27836 was published on 2026-02-27 and last updated on 2026-06-17.

CVE-2026-27836

CVE-2026-27836 is a high-severity vulnerability in Phpmyfaq with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-862.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (33rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-9059
Weakness: CWE-862
Affected product: Phpmyfaq
Published: 2026-02-27
Last modified: 2026-06-17

Description

phpMyFAQ is an open source FAQ web application. Prior to version 4.0.18, the WebAuthn prepare endpoint (`/api/webauthn/prepare`) creates new active user accounts without any authentication, CSRF protection, captcha, or configuration checks. This allows unauthenticated attackers to create unlimited user accounts even when registration is disabled. Version 4.0.18 fixes the issue.

Frequently asked questions

What is CVE-2026-27836?: phpMyFAQ is an open source FAQ web application. Prior to version 4.0.18, the WebAuthn prepare endpoint (`/api/webauthn/prepare`) creates new active user accounts without any authentication, CSRF protection, captcha, or configuration checks. This allows unauthenticated attackers to create unlimited user accounts even when registration is disabled. Version 4.0.18 fixes the issue.
How severe is CVE-2026-27836?: CVE-2026-27836 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2026-27836 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-27836?: CVE-2026-27836 affects Phpmyfaq. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-27836?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-27836 have an EU (EUVD) identifier?: Yes. CVE-2026-27836 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-9059.
When was CVE-2026-27836 published?: CVE-2026-27836 was published on 2026-02-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:phpmyfaq:phpmyfaq:*:*:*:*:*:*:*:*

More vulnerabilities in Phpmyfaq

CVE-2023-5865 — Critical (CVSS 9.8): Insufficient Session Expiration in GitHub repository thorsten/phpmyfaq prior to 3.2.2.
CVE-2023-5227 — Critical (CVSS 9.8): Unrestricted Upload of File with Dangerous Type in GitHub repository thorsten/phpmyfaq prior to 3.1.8.
CVE-2023-4006 — Critical (CVSS 9.8): Improper Neutralization of Formula Elements in a CSV File in GitHub repository thorsten/phpmyfaq prior to 3.1.16.
CVE-2023-2429 — Critical (CVSS 9.8): Improper Access Control in GitHub repository thorsten/phpmyfaq prior to 3.1.13.
CVE-2023-0311 — Critical (CVSS 9.8): Improper Authentication in GitHub repository thorsten/phpmyfaq prior to 3.1.10.
CVE-2023-0307 — Critical (CVSS 9.8): Weak Password Requirements in GitHub repository thorsten/phpmyfaq prior to 3.1.10.

All CVEs affecting Phpmyfaq →

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