CVE-2026-25227 is a critical vulnerability classified under CWE-94 (Improper Control of Generation of Code, or Code Injection) found in the open-source identity provider authentik. The flaw exists in the handling of delegated permissions related to property mappings and expression policies. Specifically, users granted the permissions 'Can view * Property Mapping' or 'Can view Expression Policy' can exploit a test endpoint intended for previewing property mappings or policies to execute arbitrary code within the authentik server container. This means an attacker with these permissions can run malicious code on the server hosting authentik, potentially leading to full system compromise. The vulnerability affects authentik versions starting from 2021.3.1 up to versions before 2025.8.6, 2025.10.4, and 2025.12.4, with patches released in those latter versions. The CVSS v3.1 score of 9.1 reflects the vulnerability's critical nature, with network attack vector, low attack complexity, high privileges required, no user interaction, and scope change indicating that the exploit can affect resources beyond the initial component. The vulnerability impacts confidentiality, integrity, and availability, allowing attackers to execute arbitrary code, modify or steal sensitive data, and disrupt services. Although no exploits are currently known in the wild, the presence of a test endpoint that facilitates code execution makes this vulnerability particularly dangerous if discovered by malicious actors. Organizations using authentik as an identity provider must assess their deployment versions and apply patches promptly to mitigate risk.

For European organizations, the impact of CVE-2026-25227 is significant due to the critical role identity providers like authentik play in authentication and authorization processes. Exploitation could lead to unauthorized access to sensitive systems, data breaches, and disruption of authentication services, potentially affecting business operations and compliance with regulations such as GDPR. The ability to execute arbitrary code on the authentik server container could allow attackers to pivot within networks, escalate privileges, and compromise additional systems. This is especially concerning for sectors with high security requirements such as finance, healthcare, government, and critical infrastructure. The vulnerability's exploitation could also undermine trust in identity management systems, leading to reputational damage and financial losses. Given the widespread use of open-source identity solutions in Europe, the threat extends to a broad range of organizations, including SMEs and large enterprises.

1. Immediate patching: Upgrade authentik installations to versions 2025.8.6, 2025.10.4, or 2025.12.4 where the vulnerability is fixed. 2. Permission auditing: Review and restrict delegated permissions, especially 'Can view * Property Mapping' and 'Can view Expression Policy', limiting them to trusted administrators only. 3. Network segmentation: Isolate authentik servers within secure network zones to reduce exposure to untrusted users. 4. Monitoring and logging: Enable detailed logging of authentik server activity and monitor for unusual access patterns or attempts to use the test endpoint. 5. Disable or restrict access to the test endpoint if possible, or implement additional authentication and authorization controls around it. 6. Conduct regular security assessments and penetration testing focused on identity provider components. 7. Employ runtime application self-protection (RASP) or web application firewalls (WAF) to detect and block suspicious code injection attempts targeting authentik. 8. Educate administrators about the risks of delegated permissions and enforce the principle of least privilege.