7.5

CVE-2026-27836: phpmyfaq Missing Authorization

CVSS: 7.5v3.1HighAnalyzed
Published 27-02-2026Last modified 03-03-2026
Open JSON

Vulnerability summary

CVE-2026-27836 is a high (CVSS 7.5) Missing Authorization vulnerability in phpmyfaq. EPSS estimates a 0.51% chance of exploitation in the next 30 days, higher than 42.1% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
40/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.51%
0%100%
Low · +0.09 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github

Timeline

  1. 27-02-2026
    PublishedVulnerability first disclosed.
  2. 03-03-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.51%

Chance of exploitation in the next 30 days

Percentile

42%

Versus all other CVEs

30-day change

+0.09 pp

From 0.41% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.51%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • githubUnverified

    Phpmyfaq

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Phpmyfaq1 product
Thorsten1 product

2 vendors · 2 products

References

2 links