grpc-swift is the Swift language implementation of gRPC, a remote procedure call (RPC) framework. Prior to version 1.7.2, a grpc-swift server is vulnerable to a denial of service attack via a reachable assertion. This is due to incorrect logic when handling GOAWAY frames. The attack is low-effort: it takes very little resources to construct and send the required sequence of frames. The impact on availability is high as the server will crash, dropping all in flight connections and requests. This issue is fixed in version 1.7.2. There are currently no known workarounds.
The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Grpc_swift | Linuxfoundation | * | 1.7.2 (excluding) |
While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, it can still lead to a denial of service. For example, if a server handles multiple simultaneous connections, and an assert() occurs in one single connection that causes all other connections to be dropped, this is a reachable assertion that leads to a denial of service.