CVE-2026-100667 (GCVE-0-2026-100667)

Vulnerability from cvelistv5 – Published: 2026-09-26 13:23 – Updated: 2026-09-28 18:14
VLAI
Title
grav-plugin-login 3.8.7 through 3.9.6 Two-Factor Authentication Bypass
Summary
grav-plugin-login (the Grav CMS Login plugin) versions >= 3.8.7 and < 3.9.7 allow the two-factor authentication challenge to be bypassed for content gated by the authenticated() Twig function or the [authenticated] shortcode. On sites with 2FA enabled, Login::isAuthenticated() checked only the session flag indicating that the password step had succeeded, not the flag indicating that login had completed, so a session sitting at the 2FA code prompt was treated as fully authenticated. An attacker who knows a member's password but cannot answer that member's second factor can therefore read member-only content rendered by the no-argument authenticated() or group authenticated(null, 'group') forms and by [authenticated]; the inverse [guest] shortcode is likewise evaluated too early. Impact is limited to disclosure of that content: the attacker does not obtain a completed session, cannot access pages protected by an access: rule, and cannot act as the user. The authenticated('some.permission') form, which goes through UserObject::authorize(), is not affected. Fixed in grav-plugin-login 3.9.7.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-28 18:12 UTC
CWE
  • CWE-304 - Missing Critical Step in Authentication
Assigner
References
Impacted products
Vendor Product Version CPE status
getgrav grav Affected: 3.8.7 , < 3.9.7 (semver)
Unaffected: 3.9.7 (semver)
    cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-09 00:00
Credits
geoffrey-diederichs
Show details on NVD website
To clipboard 

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