Horizon Alert
Summary of the vulnerability and why it matters
Concrete CMS allows an attacker to trigger core system updates by exploiting a flaw in how security tokens are validated. This vulnerability could enable an attacker to force the system to update to a version they specify. For this to be exploitable, an authenticated user must be present and an update version must be available.
- Vulnerable component: Concrete CMS dashboard
- Core weakness: Unverified security token
- Main business impact: Unauthorized system updates
Attack Path
How an attacker could exploit the issue
This vulnerability allows an attacker to trigger a core Concrete CMS update by exploiting a missing validation check. The Content Management System (CMS) generates a security token for a form, but the server-side code responsible for processing the update request fails to validate this token. An attacker can craft a malicious web page that, when visited by a logged-in CMS administrator, sends a specially designed request to the CMS. This request bypasses the security check and forces the CMS to update to a version specified by the attacker. The attack requires the victim to be logged into the CMS dashboard and for a valid update to be available.
- Vulnerability exposed online.
- Attacker sends malicious POST request.
- Result is attacker-controlled CMS update.
Live Threat
Current exploitation, exposure, and threat context
This vulnerability in Concrete CMS allows an attacker to trigger core updates by exploiting a missing token validation. An attacker could force a content management system to update to a version they specify, potentially disrupting operations or introducing further risks. The vulnerability requires specific conditions to be met for exploitation.
- Likely attacker skill level: Difficult
- Required access or conditions: Active administrator session
- Business risk or urgency: Moderate
Priority actions
Operational Fix
Recommended remediation, mitigation, and detection steps
This vulnerability allows an unauthenticated attacker to trigger a core Concrete CMS update by crafting a malicious POST request. The issue arises because the system's security token is emitted but not validated before processing the update. This could lead to an attacker forcing a core CMS update to a version they control, potentially impacting the integrity and availability of the affected system. The vendor has released a fix for this vulnerability.
- Identify Concrete CMS installations at risk.
- Restrict access to the update function if possible.
- Apply the vendor fix and confirm its implementation.
- Monitor systems for unexpected update activity.
