GHSA-gw2x-q739-qhcr RustFS gRPC GetMetrics deserialization panic enables remote DoS

• crates.io rustfs: >= 1.0.0-alpha.13, < 1.0.0-alpha.78 → fixed in 1.0.0-alpha.78

Summary A malformed gRPC `GetMetrics` request causes `get_metrics` to `unwrap()` failed deserialization of `metric_type`/`opts`, panicking the handler thread and enabling remote denial of service of the metrics endpoint. Details • Vulnerable code: `rustfs/src/storage/tonic_service.rs:1775-1782`: • `MetricType` and `CollectMetricsOpts` are deserialized with `Deserialize::deserialize(...).unwrap()` from client-supplied bytes. • Malformed `metric_type`/`opts` (e.g., empty or truncated rmp-serde payloads) trigger `InvalidMarkerRead` and panic. • Reachability: same TCP listener as S3 (default `:9000`); only a static interceptor token `authorization: rustfs rpc` is checked in `server/http.rs:677`. • Impact scope: panic terminates the worker handling the request, causing metrics service interruption and potential process instability. PoC rustfs-grpc-metrics-invalid-metric-type-panic-poc.tar.gz 1) Start RustFS (example local dev): ```bash mkdir -p /tmp/rustfs-data1 /tmp/rustfs-data2 RUSTFS_ACCESS_KEY=devadmin RUSTFS_SECRET_KEY=devadmin \ cargo run --bin rustfs -- --address 0.0.0.0:9000 \ /tmp/rustfs-data1 /tmp/rustfs-data2 ``` 2) From `rustfs-grpc-metrics-invalid-metric-type-panic-poc/`, run: ```bash ENDPOINT=127.0.0.1:9000 make run or: grpcurl -plaintext \ -H 'authorization: rustfs rpc' \ -import-path ../crates/protos/src -proto node.proto \ -d '{"metric_type":"","opts":""}' \ 127.0.0.1:9000 node_service.NodeService/GetMetrics ``` 3) Observe panic in server logs at `tonic_service.rs:get_metrics` with `InvalidMarkerRead` and worker crash; client output saved to `poc-response.txt`/`poc-grpcurl.log`. Impact • Vulnerability type: remote unauthenticated (static token) denial of service via panic in gRPC handler. • Who is impacted: any deployment exposing the gRPC endpoint where an attacker can reach port 9000 and supply the known `authorization: rustfs rpc` header; metrics service is disrupted and may affect overall stability depending on runtime crash handling.