PatchTheCVECVE-2026-84432: Concrete CMS 9 through 9.5.2 did not validate an anti-CSRF token in the Boards custom slot dialog controller
CVE-2026-84432 is a medium-severity flaw (CVSS 5.3) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Concrete CMS 9 through 9.5.2 did not validate an anti-CSRF token in the Boards custom slot dialog controller (concrete/controllers/dialog/board/custom_slot.php) saveTemplate() action. The action created a board_slot_proxy Block and dispatched an AddCustomSlotToBoardCommand against a board instance while gating only on the per-resource canEditBoardContents() permission, so a crafted cross-site request could cause a user holding board-edit permiss
Why this priority
- No elevated risk signals yet
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 5.3 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | Passive |
| EPSS exploit chance | 0.2% (top 85%) |
| CISA exploited list | No |
| Weakness | CWE-352 |
| Published | 2026-09-10 |
| Last modified | 2026-09-10 |
Last updated 2026-09-10 · 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-2026-84432?
No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.
Is CVE-2026-84432 being exploited?
CVE-2026-84432 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-2026-84432 affect?
CVE-2026-84432 affects affected software. Severity is medium (CVSS 5.3). Concrete CMS 9 through 9.5.2 did not validate an anti-CSRF token in the Boards custom slot dialog controller (concrete/controllers/dialog/board/custom_slot.php) saveTemplate() action. The action created a board_slot_proxy Block and dispatc
How urgent is CVE-2026-84432?
Priority 22/100. No elevated risk signals yet.