RustFS gRPC GetMetrics deserialization panic enables remote DoS

### 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](https://github.com/user-attachments/files/24038341/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.

Source published

7 Jan 2026 18:36:23 UTC

Source modified

3 Feb 2026 03:16:17 UTC

Observed here

24 Oct 2026 13:19:54 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

Publisher rating · MODERATE