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
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.006 (44.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 44.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.006 · change: +0.003
Affected products
- Getgrav Grav — versions 2.0.11, 0, 1.4.7
Weakness classification (CWE)
References
- github.com/getgrav/grav/security/advisories/GHSA-pc8m-jxvh-vmrc (vendor-advisory)
- github.com/getgrav/grav/commit/ad9709f865b09b68798fb1ac375b484a8cc1d892 (patch)
- github.com/getgrav/grav/commit/0b384f5b0e73b1ad9dd29c70185407895ea3b09f (patch)
- github.com/getgrav/grav/commit/8071c10bc3a4743a4b8cf003dfb1644d6680c2ea (patch)
- github.com/getgrav/grav/commit/a0bf26f7e5d7a98894b7cd2b8c5afe419b264e53 (patch)
- www.vulncheck.com/advisories/grav-through-authentication-bypass-via-flex-objects (third-party-advisory)
- github.com/trilbymedia/grav-plugin-flex-objects/commit/0b384f5b0e73b1ad9dd29c70… (patch)
- github.com/getgrav/grav-plugin-api/commit/8071c10bc3a4743a4b8cf003dfb1644d6680c… (patch)
- github.com/getgrav/grav-plugin-admin2/commit/a0bf26f7e5d7a98894b7cd2b8c5afe419b… (patch)
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.