CVE-2026-111226 Netgate CVE debrief

Who should care

System administrators and security teams responsible for pfSense CE installations, especially those with Advanced Admin Access users, should assess exposure and prioritize remediation.

Why it matters

CVE-2026-111226 is a high-severity OS command injection vulnerability in Netgate pfSense CE. Authenticated users with Advanced Admin Access can execute commands as root, posing a significant risk to system integrity and data security. System administrators and security teams should immediately assess exposure, verify user access, and prioritize remediation.

• Potential for authenticated users to execute arbitrary commands as root
• Possible disruption of system operations and data integrity
• Need for verification of user access and Login Protection settings
• Requirement for prompt patching or mitigation to prevent exploitation

Technical summary

The vulnerability exists in system_advanced_admin.php and allows attackers to inject OS commands via Login Protection settings. The issue affects pfSense CE versions 2.4.5 through 2.9.0. Authenticated WebGUI users with Advanced Admin Access can execute commands as root, posing a significant risk to system integrity and data security. The vulnerability allows attackers to submit malicious values that are written unvalidated to sshguard.conf and sourced as root on restart. This can lead to potential disruption of system operations and data integrity.

Defensive priority

High priority for systems administrators and security teams responsible for pfSense CE installations, especially those with Advanced Admin Access users.

Recommended defensive actions

• Immediately review and limit Advanced Admin Access users
• Verify and restrict Login Protection settings
• Monitor for suspicious activity and implement compensating controls
• Apply vendor patches or updates as soon as available
• Review system configurations for potential exposure
• Implement additional logging and monitoring for Login Protection settings
• Verify user access and permissions for WebGUI users

Evidence notes

The CVE record and source item provide details on the vulnerability, affected versions, and potential impact. However, there is limited information on exploitation, victims, or business impact. Defenders should verify system configurations, review Login Protection settings, and monitor for suspicious activity. The vulnerability affects pfSense CE versions 2.4.5 through 2.9.0 and allows authenticated WebGUI users with Advanced Admin Access to execute commands as root via Login Protection settings.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.