Horizon Alert
Summary of the vulnerability and why it matters
This advisory concerns a vulnerability in the Grav content management system that could allow a lower-privileged administrator to gain full super-admin control. This escalation grants the ability to execute code and modify system settings, potentially impacting the integrity and availability of the system. The main concern is confirming relevance and exposure to your specific Grav instances.
- Admin users can gain full control.
- Leads to potential system compromise.
- Confirm Grav instances and exposure.
Attack Path
How an attacker could exploit the issue
An attacker could exploit this vulnerability by leveraging an existing administrative account with limited user management privileges. By manipulating the group access settings, an attacker can escalate their privileges to super-admin, granting them control over the system's scheduler and the ability to execute Twig code. This could ultimately lead to full system compromise.
- Attacker needs admin access.
- Manipulate group access field.
- Full system compromise.
Live Threat
Current exploitation, exposure, and threat context
A delegated administrator could potentially gain full super-admin privileges, enabling them to execute scheduler tasks and evaluate Twig code. This escalation is possible when the access field in the core group blueprint is not adequately protected, and a user with `admin.users` operator rights saves a group with `access[admin][super]=true`.
- Super-admin capabilities and Twig evaluation.
- Delegated admin saves a group with elevated access.
- Unauthorized system control and code execution.
Operational Fix
Recommended remediation, mitigation, and detection steps
This vulnerability affects Grav, a content management system. Given its typical deployment as a public-facing web application, the first practical step is to identify all Grav instances, assess their exposure and criticality, and confirm their accountable owners. This will inform a risk-based remediation plan, potentially involving vendor coordination or temporary risk reduction measures.
- Application owners should own the issue.
- Verify Grav instance exposure and criticality.
- Plan remediation based on identified risk.
