Calendar event duplication via missing CSRF validation
Published Sep 11, 2026 · Updated Sep 11, 2026
CSRF in Concrete CMS 9.5.2 allows remote attackers to duplicate calendar events through an authenticated user's browser. The submit() action in concrete/controllers/dialog/event/duplicate.php creates CalendarEvents and CalendarEventVersions records without validating an anti-CSRF token. Exploitation requires an authenticated user with add-event permission to submit the crafted request, and the duplicate records are created under that user's authority.
Summary
What happened
CSRF in Concrete CMS 9.5.2 allows remote attackers to duplicate calendar events through an authenticated user's browser. The submit() action in concrete/controllers/dialog/event/duplicate.php creates CalendarEvents and CalendarEventVersions records without validating an anti-CSRF token. Exploitation requires an authenticated user with add-event permission to submit the crafted request, and the duplicate records are created under that user's authority.
The record
- CVE
- CVE-2026-68526
- Published
- Sep 11, 2026
- Updated
- Sep 11, 2026
- Vendor
- Concrete CMS
- Product
- Concrete CMS
- Classifications
- CWE-352, T1204.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 11, 2026CVE publishedPublication date reported by the CVE source.
- Sep 11, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=9.5.2
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What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Technologies
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Your stack
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