fun signersMustHaveCaBitSet() {
    val attackerCa =
      HeldCertificate
        .Builder()
        .serialNumber(1L)
        .certificateAuthority(4)
        .commonName("attacker ca")
        .build()
    val attackerIntermediate =
      HeldCertificate
        .Builder()
        .serialNumber(2L)
        .certificateAuthority(3)
        .commonName("attacker")
        .signedBy(attackerCa)

from fastapi.testclient import TestClient


def test_root_path_does_not_persist_across_requests():
    app = FastAPI()

    @app.get("/")
    def read_root():  # pragma: no cover
        return {"ok": True}

    # Attacker request with a spoofed root_path
    attacker_client = TestClient(app, root_path="/evil-api")
    response1 = attacker_client.get("/openapi.json")
    data1 = response1.json()

### Hardware attacks

Physical GPUs or TPUs can also be the target of attacks. [Published
research](https://scholar.google.com/scholar?q=gpu+side+channel) shows that it
might be possible to use side channel attacks on the GPU to leak data from other
running models or processes in the same system. GPUs can also have
implementation bugs that might allow attackers to leave malicious code running

    # Return some error
    ...
```

But by using the `secrets.compare_digest()` it will be secure against a type of attacks called "timing attacks".

### Timing Attacks { #timing-attacks }

But what's a "timing attack"?

Let's imagine some attackers are trying to guess the username and password.

And they send a request with a username `johndoe` and a password `love123`.

Attackers could simply run a script to send requests to your API, no need for browser interaction, so you are probably already securing any privileged endpoints.

In that case **this attack / risk doesn't apply to you**.

This risk and attack is mainly relevant when the app runs on the **local network** and that is the **only assumed protection**.

    # Bir hata döndür
    ...
```

Ancak `secrets.compare_digest()` kullanarak, "timing attacks" denilen bir saldırı türüne karşı güvenli olursunuz.

### Timing Attacks { #timing-attacks }

Peki "timing attack" nedir?

Bazı saldırganların kullanıcı adı ve şifreyi tahmin etmeye çalıştığını düşünelim.

### CVE-2022-3172: Aggregated API server can cause clients to be redirected (SSRF)

A security issue was discovered in kube-apiserver that could allow an attacker controlled aggregated API server to redirect client traffic to any URL.  This could lead to the client performing unexpected actions as well as leaking the client's credentials to third parties. 

- Replace `go-bindata` with `//go:embed`. ([#99829](https://github.com/kubernetes/kubernetes/pull/99829), [@palnabarun](https://github.com/palnabarun))
- The `DynamicFakeClient` now exposes its tracker via a `Tracker()` function. ([#100085](https://github.com/kubernetes/kubernetes/pull/100085), [@markusthoemmes](https://github.com/markusthoemmes))

    # Devuelve algún error
    ...
```

Pero al usar `secrets.compare_digest()` será seguro contra un tipo de ataques llamados "timing attacks".

### Timing attacks { #timing-attacks }

¿Pero qué es un "timing attack"?

Imaginemos que algunos atacantes están tratando de adivinar el nombre de usuario y la contraseña.

Y envían un request con un nombre de usuario `johndoe` y una contraseña `love123`.

    # Поверніть якусь помилку
    ...
```

Але використовуючи `secrets.compare_digest()`, це буде захищено від типу атак, що називаються «атаки за часом» (timing attacks).

### Атаки за часом { #timing-attacks }

Що таке «атака за часом»?

Уявімо, що зловмисники намагаються вгадати ім'я користувача та пароль.

Вони надсилають запит з ім'ям користувача `johndoe` та паролем `love123`.