这类攻击利用了浏览器的一个事实：当请求满足以下条件时，浏览器允许脚本在不进行任何 CORS 预检的情况下直接发送请求：

- 没有 `Content-Type` 头（例如使用 `fetch()` 携带 `Blob` 作为 body）
- 且不发送任何认证凭据。

这种攻击主要在以下情况下相关：

- 应用在本地（如 `localhost`）或内网中运行
- 且应用没有任何认证，假定来自同一网络的请求都可信。

## 攻击示例 { #example-attack }

假设你构建了一个本地运行的 AI 代理。

它提供了一个 API，地址为

```
http://localhost:8000/v1/agents/multivac
```

另有一个前端，地址为

```
http://localhost:8000
```

/// tip | 提示

注意它们的主机相同。

policy grants access to buckets with name starting with example. ## In addition, grants objects read permissions on buckets starting with example. # - name: readonlyexamplepolic # statements: # - resources: # - 'arn:aws:s3:::example*/*' # actions: # - "s3:GetObject" # - resources: # - 'arn:aws:s3:::example*' # actions: # - "s3:GetBucketLocation" # - "s3:ListBucket" # - "s3:ListBucketMultipartU" ## conditionsexample policy creates all access to example bucket with aws:username="johndoe" and source ip range...

---

Good bug reports include a failing test! Writing a test helps you to isolate and describe the problem, and it helps us to fix it fast. Bug reports without a failing test or reproduction steps are likely to be closed.

Here’s an example test to get you started.

writeexamplepolicy policy grants creation or deletion of buckets with name ## starting with example. In addition, grants objects write permissions on buckets starting with ## example. # - name: writeexamplepolicy # statements: # - resources: # - 'arn:aws:s3:::example*/*' # actions: # - "s3:AbortMultipartUpload" # - "s3:GetObject" # - "s3:DeleteObject" # - "s3:PutObject" # - "s3:ListMultipartUploadP" # - resources: # - 'arn:aws:s3:::example*' # actions: # - "s3:CreateBucket" # - "s3:DeleteBucket" # - "s3:GetBucketLocation"...

writeexamplepolicy policy grants creation or deletion of buckets with name ## starting with example. In addition, grants objects write permissions on buckets starting with ## example. # - name: writeexamplepolicy # statements: # - resources: # - 'arn:aws:s3:::example*/*' # actions: # - "s3:AbortMultipartUpload" # - "s3:GetObject" # - "s3:DeleteObject" # - "s3:PutObject" # - "s3:ListMultipartUploadP" # - resources: # - 'arn:aws:s3:::example*' # actions: # - "s3:CreateBucket" # - "s3:DeleteBucket" # - "s3:GetBucketLocation"...

writeexamplepolicy policy grants creation or deletion of buckets with name ## starting with example. In addition, grants objects write permissions on buckets starting with ## example. # - name: writeexamplepolicy # statements: # - resources: # - 'arn:aws:s3:::example*/*' # actions: # - "s3:AbortMultipartUpload" # - "s3:GetObject" # - "s3:DeleteObject" # - "s3:PutObject" # - "s3:ListMultipartUploadP" # - resources: # - 'arn:aws:s3:::example*' # actions: # - "s3:CreateBucket" # - "s3:DeleteBucket" # - "s3:GetBucketLocation"...

writeexamplepolicy policy grants creation or deletion of buckets with name ## starting with example. In addition, grants objects write permissions on buckets starting with ## example. # - name: writeexamplepolicy # statements: # - resources: # - 'arn:aws:s3:::example*/*' # actions: # - "s3:AbortMultipartUpload" # - "s3:GetObject" # - "s3:DeleteObject" # - "s3:PutObject" # - "s3:ListMultipartUploadP" # - resources: # - 'arn:aws:s3:::example*' # actions: # - "s3:CreateBucket" # - "s3:DeleteBucket" # - "s3:GetBucketLocation"...

     *
     * ```kotlin
     *     val hash = body.sha256().hex()
     *     val query = Request
     *         .Builder()
     *         .query(body)
     *         .url("https://example.com/query")
     *         .cacheUrlOverride("https://example.com/query/$hash".toHttpUrl())
     *         .build()
     * ```
     *
     * @see cacheUrlOverride
     */
    open fun query(body: RequestBody): Builder = method("QUERY", body)

/// tip | 팁

여기서 `tokenUrl="token"`은 아직 만들지 않은 상대 URL `token`을 가리킵니다. 상대 URL이므로 `./token`과 동일합니다.

상대 URL을 사용하므로, 예를 들어 API가 `https://example.com/`에 있다면 `https://example.com/token`을 가리킵니다. 하지만 API가 `https://example.com/api/v1/`에 있다면 `https://example.com/api/v1/token`을 가리킵니다.

상대 URL을 사용하는 것은 [프록시 뒤에서](../../advanced/behind-a-proxy.md) 같은 고급 사용 사례에서도 애플리케이션이 계속 동작하도록 보장하는 데 중요합니다.

///

1. Run the tool with:

```
go run docs/auditlog/auditlog-echo.go
```

The listen port has a default value (8080), but can be set with the `-port` flag.

2. Configure audit logging in MinIO with for example:

```
mc admin config set myminio audit_webhook enable=on endpoint=http://localhost:8080
```