Auth bypass in Getgrav Grav
CVE-2026-72831
The Flex Objects plugin (through 1.4.6, tested with Grav 2.0.11) contains an incorrect authorization vulnerability in its Flex Objects API. FlexApiController::update() checks only the general Flex directory permission and does not apply the additional target/field/super-admin checks enforced by the dedicated Users and Groups API controllers. An authenticated account with api.access, admin.login, and users.update permissions (but without api.users.write or admin.super) can use the generic /api/v1/flex-objects/user-accounts endpoint to change a super administrator's password, or the /api/v1/flex-objects/user-groups endpoint to grant its group admin.super, resulting in full site takeover. Fixed in Flex Objects 1.4.7.
Vulnerability class: Broken Access Control
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Getgrav Grav — versions 2.0.11, 0, 1.4.7
Weakness classification (CWE)
References
- disclosure@vulncheck.com (vendor-advisory)
- disclosure@vulncheck.com (patch)
- disclosure@vulncheck.com (patch)
- disclosure@vulncheck.com (patch)
- disclosure@vulncheck.com (patch)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-72831?
- CVE-2026-72831 is a high-severity vulnerability in Getgrav Grav, classified under Incorrect Authorization. CVSS score: 8.8/10. Published 2026-08-14.
- How severe is CVE-2026-72831?
- High severity. CVSS v3 base score is 8.8 out of 10.