Project and affected component
The agent-side Control Interface authorizer and its evaluation of field masks against configured allow rules.
Security boundary
A workload granted access to a limited state subtree should not be able to read or modify cluster state outside that scope.
Vulnerability class
Incorrect authorization resulting in unauthorized disclosure or modification of cluster state.
Root cause
Multi-segment allow rules beginning with a wildcard were evaluated incorrectly when a request supplied an empty field mask. The empty mask could be treated as matching the scoped rule even though it selected broader state than the rule was intended to authorize. A rule consisting only of a wildcard has intentionally unrestricted semantics. Multi-segment wildcard rules should not inherit that behavior.
Validation method
Source review traced the authorization decision from the incoming request to field-mask evaluation. Controlled reproductions confirmed the behavior across affected versions, negative controls separated intended wildcard behavior from the bypass, and the maintainer fix was retested against the same cases.
Practical impact
A workload operating with scoped Control Interface permissions could read complete cluster state or modify workloads and configuration outside its authorized subtree.
Disclosure status
The Eclipse Foundation assigned CVE-2026-84173 and GHSA-rp6v-x3q5-cp2g. The issue was fixed in Eclipse Ankaios v1.0.2. The public CVE record credits Ievgen Bondarenko as the reporter.
Remediation
Treat a standalone wildcard and a multi-segment wildcard rule as different authorization cases. Reject empty field masks unless unrestricted state access was explicitly granted, and upgrade affected deployments to the fixed release.