CVE intelligence and bounded remediation
CVE-2021-22966 — Privilege escalation from Editor to Admin using Groups in Concrete CMS versions 8.5.6 and below
Privilege escalation from Editor to Admin using Groups in Concrete CMS versions 8.5.6 and below. If a group is granted "view" permissions on the bulkupdate page, then users in that group can escalate to being an administrator with a specially crafted curl. Fixed by adding a check for group permissions before allowing a group to be moved. Concrete CMS Security team CVSS scoring: 7.1 AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:HCredit for discovery: "Adrian Tiron from FORTBRIDGE ( https://www.fortbridge.co.uk/ )"This fix is also in Concrete version 9.0.0
- Severity
- High
- CVSS
- 8.8 (3.1)
- Published
- 2021-11-19
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-863
Affected products
- concretecms / concrete_cms
Matched remediation archetype
Authorization bypass, IDOR, and cross-tenant access
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Map object and action authorization checks across API, UI, batch, import/export, and background-job paths.
- Identify tenant, ownership, role, and policy boundaries for affected resources and administrative operations.
- Use synthetic fixtures to compare intended access matrices without accessing another user's real data.
Remediate safely
- Enforce server-side authorization at each resource access and state transition using the authenticated principal and trusted tenant context.
- Scope data queries by tenant and ownership; treat client-supplied identifiers, roles, and policy claims as untrusted.
- Add deny-by-default policy tests for horizontal and vertical access across every affected transport.
Authoritative sources
Complete CVE record and remediation plan
The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.