CVE-2026-18675
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk17th percentile - higher than 17% of all known CVEs
Summary
The dataplane token validator in kuma-cp performs an unchecked Go type assertion on the JWT kid header. A token whose kid is a JSON number decodes as a float64 and triggers a runtime panic before any signature, claims, or authorization check runs.
Risk Assessment
The panic terminates the entire kuma-cp process, HTTP API, health and readiness endpoints, and xDS. Unauthenticated access to the dataplane gRPC server can trigger the crash with a malformed token.
Recommendation
Upgrade kuma-cp to a patched version or apply a workaround by restricting access to the gRPC server.
Original NVD description (English source)
The dataplane token validator in kuma-cp performs an unchecked Go type assertion on the JWT kid header. A token whose kid is a JSON number decodes as a float64 and triggers a runtime panic before any signature, claims, or authorization check runs. The panic terminates the entire kuma-cp process, HTTP API, the health and readiness endpoints, and xDS. Unauthenticated access to the dataplane gRPC server can trigger the crash with a malformed token A single request is a transient interruption; sustaining an outage requires repeated requests.