diff --git a/docs/overview/threat-model.md b/docs/overview/threat-model.md index a5adf8025d..442d51985c 100644 --- a/docs/overview/threat-model.md +++ b/docs/overview/threat-model.md @@ -52,7 +52,7 @@ As part of signing in with an identity resolver, a Backstage Token is issued con The token is used to prove the identity of the user within the Backstage system, and is used throughout Backstage plugins to control access. It is important that the ownership resolution logic is consistent across the entire Backstage ecosystem, with no possibility of misinterpreting the ownership information. -For cross backend communication the Backstage Token is typically forwarded or in strict backend to backend communication without a user party the backend itself issues a service token based on a pre-shared secret which is then validated on the receiving end. There are no unique service identities tied to these tokens at this point, meaning the tokens can be used across all services in a Backstage installation, this is something that we aim to improve in the future. +For cross-backend communication, the Backstage Token is typically forwarded or, in strict backend-to-backend communication without a user party, the backend itself issues a service token based on a pre-shared secret which is then validated on the receiving end. There are no unique service identities tied to these tokens at this point, meaning the tokens can be used across all services in a Backstage installation. This is something that we aim to improve in the future. Backstage also supports authentication through a proxy where the user identity is read from the incoming request from the proxy, which has been decorated by an authenticating reverse proxy such as [AWS ALB](https://aws.amazon.com/elasticloadbalancing/application-load-balancer/). The following proxy auth providers verify the signature of incoming requests, and are therefore safe to deploy with direct access by users: `awsAlb`, `cfAccess`, and `gcpIap`. Providers like `oauth2Proxy` does not verify the incoming request and can therefore be spoofed by a malicious internal user to supply the `auth` backend with forged identity information. It’s therefore highly recommended to restrict access to the `oauth2Proxy` endpoints, or use a different provider.