GHSA-qv3x-mffx-9gw8 CVE-2026-8238
Concrete CMS is vulnerable to IDOR
- Severity
- 0.0 / 10
- Medium · CVSS 4.0
- Exploit chance (EPSS)
- 0.20%
- Chance of exploitation in the next 30 days. Higher than 10.03% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-862 Missing Authorization
- Fix
9.5.1- Upgrade concrete5/concrete5 to this version or later
Description
Concrete CMS 9.5.0 and below is vulnerable to IDOR. The '/ccm/frontend/conversations/message_page' endpoint returns the full content of any conversation message. An unauthenticated attacker can enumerate all conversation messages, including messages from restricted pages, member-only areas, and the moderation queue. File attachments with download URLs are also exposed.
Affected versions
Packagist
| Package | Vulnerable | Fixed in |
|---|---|---|
| concrete5/concrete5 | < 9.5.1 |
9.5.1 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
concrete5/concrete5 Packagist → 9.5.1
- composer
composer require concrete5/concrete5:^9.5.1
Severity breakdown
CVSS 4.0 0.0
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
- Attack vector
- Network
- Attack complexity
- Low
- Attack requirements
- Present
- Privileges required
- None
- User interaction
- None
- Confidentiality (vulnerable system)
- Low
- Integrity (vulnerable system)
- None
- Availability (vulnerable system)
- None
- Confidentiality (subsequent systems)
- None
- Integrity (subsequent systems)
- None
- Availability (subsequent systems)
- None
CVSS 3.1 5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Weakness
CWE-862: Missing Authorization
The product does not perform an authorization check when an actor attempts to access a resource or perform an action.
How to prevent it
- Architecture and Design: Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) [REF-229] to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
- Architecture and Design: Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor [REF-7].
- Architecture and Design: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
- Architecture and Design: For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page. One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.
- System Configuration, Installation: Use the access control capabilities of your operating system and server environment and define your access control lists accordingly. Use a "default deny" policy when defining these ACLs.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-g82f-9pw7-773w Concrete CMS: PHP Object Injection via unserialize() calls | High | Also affects concrete5/concrete5 |
| GHSA-52pr-7vmf-2w7x Concrete CMS is vulnerable to PHP Object Injection via unserialize() calls in the Workflow, Form block, and File/Set components | High | Also affects concrete5/concrete5 |
| GHSA-q9fm-mpg8-8jqm Concrete CMS is vulnerable to Stored XSS via page name in the Atomik theme | Medium | Also affects concrete5/concrete5 |
| GHSA-jqvq-gv67-3567 Concrete CMS is vulnerable to IDOR + wrong-authorization-level in the Express association Reorder dialog | Medium | Also affects concrete5/concrete5 |
| GHSA-xjg6-5v39-v7fc Concrete CMS is vulnerable to CSRF via Backend\File::approveVersion | Medium | Also affects concrete5/concrete5 |
| GHSA-44q4-354f-c826 Concrete CMS is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file approveVersion() | Medium | Also affects concrete5/concrete5 |
| GHSA-6qjh-p324-694f Concrete CMS is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file rescanMultiple() | High | Also affects concrete5/concrete5 |
| GHSA-6fxm-r8p3-mx5c Concrete CMS is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file rescan() | High | Also affects concrete5/concrete5 |
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