Concrete CMS up to 9.5.0 Message get_rating authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Concrete CMS up to 9.5.0. The impacted element is an unknown function of the file /ccm/frontend/conversations/get_rating of the component Message Handler. Such manipulation leads to authorization. This vulnerability is listed as CVE-2026-8239. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in Concrete CMS up to 9.5.0 and classified as problematic. Affected by this issue is some unknown functionality of the file /ccm/frontend/conversations/get_rating of the component Message Handler. The manipulation with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. Impacted is confidentiality. CVE summarizes:

Concrete CMS 9.5.0 and below is vulnerable to IDOR. The '/ccm/frontend/conversations/get_rating' endpoint confirms existence and returns rating score for any message by ID. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with Vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Tristan Madani for reporting.

The weakness was presented by Tristan Madani. The advisory is shared for download at documentation.concretecms.org. This vulnerability is handled as CVE-2026-8239 since 05/09/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 05/22/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-862 / CWE-863 / CWE-285
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

05/09/2026 CVE reserved
05/22/2026 +13 days Advisory disclosed
05/22/2026 +0 days VulDB entry created
05/22/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: documentation.concretecms.org
Researcher: Tristan Madani
Status: Not defined

CVE: CVE-2026-8239 (🔒)
GCVE (CVE): GCVE-0-2026-8239
GCVE (VulDB): GCVE-100-365108

Entryinfo

Created: 05/22/2026 06:07
Changes: 05/22/2026 06:07 (67)
Complete: 🔍
Cache ID: 216::103

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