PatchTheCVECVE-2026-18122: Concrete CMS 9.2.0 to 9.5.2 Express REST API list endpoint exposes restricted Express entries via Missing Auth
CVE-2026-18122 is a medium-severity flaw (CVSS 6.0) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Concrete CMS 9.2.0 to 9.5.2 Express REST API list endpoint exposes restricted Express entries via Missing Authorization; the Concrete CMS REST API's Express entry collection endpoint disabled the per-entry view permission check. An OAuth token with read scope for an Express entity could enumerate entries that its user context lacked permission to view, disclosing each entry's public identifier, URL, label, dates, and any attribute or associated-e
Why this priority
- No elevated risk signals yet
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 6.0 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | Low |
| User interaction | None |
| EPSS exploit chance | 0.4% (top 67%) |
| CISA exploited list | No |
| Weakness | CWE-862 |
| Published | 2026-09-11 |
| Last modified | 2026-09-11 |
Last updated 2026-09-11 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-18122?
No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.
Is CVE-2026-18122 being exploited?
CVE-2026-18122 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-18122 affect?
CVE-2026-18122 affects affected software. Severity is medium (CVSS 6.0). Concrete CMS 9.2.0 to 9.5.2 Express REST API list endpoint exposes restricted Express entries via Missing Authorization; the Concrete CMS REST API's Express entry collection endpoint disabled the per-entry view permission check. An OAuth to
How urgent is CVE-2026-18122?
Priority 29/100. No elevated risk signals yet.