Unauthenticated rating disclosure via unchecked message IDs
Published May 21, 2026 · Updated May 21, 2026
IDOR in the get_rating endpoint in Concrete CMS 5.0 through 9.5.0 allows remote attackers to read message rating scores by ID. The endpoint accepts a message identifier without enforcing authorization, confirms whether that message exists, and returns its rating score. No authentication or user interaction is required, but exploitation depends on supplying a valid message identifier and exposes only message existence and rating data.
Summary
What happened
IDOR in the get_rating endpoint in Concrete CMS 5.0 through 9.5.0 allows remote attackers to read message rating scores by ID. The endpoint accepts a message identifier without enforcing authorization, confirms whether that message exists, and returns its rating score. No authentication or user interaction is required, but exploitation depends on supplying a valid message identifier and exposes only message existence and rating data.
The record
- CVE
- CVE-2026-8239
- Published
- May 21, 2026
- Updated
- May 21, 2026
- Vendor
- Concrete CMS
- Product
- Concrete CMS
- Classifications
- CWE-862, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 21, 2026CVE publishedPublication date reported by the CVE source.
- May 21, 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=5.0 <=9.5.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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