CVE-2026-22536 is a vulnerability classified under CWE-269 (Improper Privilege Management) affecting EFACEC QC 60/90/120 products, specifically version 8. The root cause is the absence of proper permission controls for a user labeled XXX in the sudoers configuration, which allows unrestricted privilege escalation. This means that a local user can execute commands with elevated privileges without authentication or user interaction, due to overly permissive sudoers rules. The vulnerability does not require network access (AV:L - local attack vector) but has low attack complexity (AC:L), no privileges required (PR:N), and no user interaction (UI:N). The impact on confidentiality, integrity, and availability is high (VC:H, VI:H, VA:H), as an attacker can gain full administrative control, potentially leading to data breaches, system manipulation, or denial of service. The vulnerability is currently not known to be exploited in the wild, but the high CVSS 4.0 score of 8.6 reflects its critical nature. EFACEC QC products are used in industrial and infrastructure environments, making this vulnerability particularly concerning for operational technology (OT) environments. The lack of available patches necessitates immediate configuration reviews and compensating controls to mitigate risk.

For European organizations, especially those in critical infrastructure sectors such as energy, manufacturing, and transportation that utilize EFACEC QC 60/90/120 systems, this vulnerability poses a significant risk. Unauthorized privilege escalation can lead to full system compromise, allowing attackers to manipulate control systems, disrupt operations, or exfiltrate sensitive data. The high impact on confidentiality, integrity, and availability could result in operational downtime, safety hazards, and regulatory non-compliance. Given EFACEC's strong presence in Portugal and other European industrial markets, the threat could affect national infrastructure resilience. Additionally, organizations with limited local user access controls or insufficient monitoring are at greater risk. The absence of known exploits in the wild provides a window for proactive defense, but the vulnerability's ease of exploitation and high impact demand urgent attention.

1. Immediately audit and restrict the sudoers file configurations on all EFACEC QC 60/90/120 version 8 systems to ensure no users have unrestricted privilege escalation capabilities. 2. Implement the principle of least privilege by removing or limiting sudo permissions for the user XXX or any similarly configured accounts. 3. Employ host-based intrusion detection systems (HIDS) to monitor for unusual privilege escalation attempts or suspicious command executions. 4. Enforce strict local user account management and disable unnecessary local accounts to reduce attack surface. 5. If possible, isolate EFACEC QC systems from general IT networks to limit local access to trusted personnel only. 6. Maintain detailed logging and regularly review logs for signs of misuse. 7. Engage with EFACEC for official patches or updates and apply them promptly once available. 8. Conduct regular security training for administrators managing these systems to recognize and prevent misconfigurations. 9. Consider deploying application whitelisting or mandatory access controls (e.g., SELinux, AppArmor) to limit unauthorized command execution. 10. Develop and test incident response plans specific to privilege escalation scenarios in OT environments.