Summary
authentik API serializers may return stored credentials to accounts that have permission to view certain configurations, even when those accounts are not authorized to read secrets or modify the configuration. The issue becomes risky when configuration view access is granted to users who should not see embedded client secrets, shared secrets, provisioning credentials, or other stored authentication material.
Affected context
The vulnerability can occur in authentik deployments where configuration objects containing secrets are viewable by accounts that are not intended to read those secrets. Affected areas may include one-time code delivery by mail or SMS, outbound provisioning targets, device trust integrations, identity sources, Kubernetes outposts, applications using client or shared secrets, and applications using proxy providers. Deployments in which every viewer is already authorized to read the associated credentials are less exposed.
Exploit preconditions
- Attack surface: authentik configuration APIs and their serialized responses
- Required access: An account with permission to view an affected configuration
- Trigger point: Retrieval of the configuration through an API or administrative interface
- Why exploitation is possible: The serializer includes stored credential fields based on configuration visibility rather than the caller's authorization to read secrets
Why this happens
The underlying flaw is an authorization and data-minimization failure in API serialization. Sensitive credential fields are returned whenever a caller can view the related configuration, without separately enforcing permission to access the secrets themselves. This maps primarily to CWE-200, Exposure of Sensitive Information, and is also related to CWE-522, Insufficiently Protected Credentials, because stored authentication material is disclosed to unauthorized viewers.
Potential impact
- Attackers may obtain client secrets, shared secrets, or integration credentials.
- Exposed credentials could enable impersonation or unauthorized API access.
- Compromised provisioning or identity-source credentials could enable access to connected systems.
- Device trust, proxy, or outpost secrets could be misused to weaken access controls.
- Credential disclosure could support lateral movement or persistence.
General mitigation guidance
Mitigation generally focuses on separating configuration visibility from
secret visibility and minimizing sensitive data returned by APIs.
Common defensive patterns include:
- Redacting or omitting credentials from ordinary configuration serializers.
- Applying explicit, field-level authorization checks before returning secrets.
- Returning secret metadata or write-only placeholders instead of stored values.
- Restricting configuration view permissions according to least privilege.
- Limiting credential scope and privileges in connected systems.
- Rotating credentials when unauthorized disclosure may have occurred.
- Treating administrative API responses as sensitive and protecting them with strong access controls.
How teams detect issues like this
Organizations can look for this issue through:
- Static analysis and code review checks for serializers that expose secret-bearing fields.
- Tests that compare configuration-view permissions with secret-read permissions.
- API contract tests verifying that credentials are omitted or redacted for unauthorized roles.
- Monitoring for unusual configuration reads and access to administrative endpoints.
- Policy enforcement requiring explicit annotations or allowlists for fields permitted in API responses.
- Automated security review tools that identify credential-like fields returned by serializers.
