mirror of
https://github.com/HackTricks-wiki/hacktricks-cloud.git
synced 2025-12-27 05:03:31 -08:00
86 lines
5.5 KiB
Markdown
86 lines
5.5 KiB
Markdown
# AWS - API Gateway Unauthenticated Enum
|
|
|
|
{% hint style="success" %}
|
|
Learn & practice AWS Hacking:<img src="../../../.gitbook/assets/image (1) (1) (1) (1).png" alt="" data-size="line">[**HackTricks Training AWS Red Team Expert (ARTE)**](https://training.hacktricks.xyz/courses/arte)<img src="../../../.gitbook/assets/image (1) (1) (1) (1).png" alt="" data-size="line">\
|
|
Learn & practice GCP Hacking: <img src="../../../.gitbook/assets/image (2) (1).png" alt="" data-size="line">[**HackTricks Training GCP Red Team Expert (GRTE)**<img src="../../../.gitbook/assets/image (2) (1).png" alt="" data-size="line">](https://training.hacktricks.xyz/courses/grte)
|
|
|
|
<details>
|
|
|
|
<summary>Support HackTricks</summary>
|
|
|
|
* Check the [**subscription plans**](https://github.com/sponsors/carlospolop)!
|
|
* **Join the** 💬 [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** us on **Twitter** 🐦 [**@hacktricks\_live**](https://twitter.com/hacktricks_live)**.**
|
|
* **Share hacking tricks by submitting PRs to the** [**HackTricks**](https://github.com/carlospolop/hacktricks) and [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repos.
|
|
|
|
</details>
|
|
{% endhint %}
|
|
|
|
### API Invoke bypass
|
|
|
|
According to the talk [Attack Vectors for APIs Using AWS API Gateway Lambda Authorizers - Alexandre & Leonardo](https://www.youtube.com/watch?v=bsPKk7WDOnE), Lambda Authorizers can be configured **using IAM syntax** to give permissions to invoke API endpoints. This is taken [**from the docs**](https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-control-access-using-iam-policies-to-invoke-api.html):
|
|
|
|
```json
|
|
{
|
|
"Version": "2012-10-17",
|
|
"Statement": [
|
|
{
|
|
"Effect": "Permission",
|
|
"Action": [
|
|
"execute-api:Execution-operation"
|
|
],
|
|
"Resource": [
|
|
"arn:aws:execute-api:region:account-id:api-id/stage/METHOD_HTTP_VERB/Resource-path"
|
|
]
|
|
}
|
|
]
|
|
}
|
|
```
|
|
|
|
The problem with this way to give permissions to invoke endpoints is that the **"\*" implies "anything"** and there is **no more regex syntax supported**.
|
|
|
|
Some examples:
|
|
|
|
* A rule such as `arn:aws:execute-apis:sa-east-1:accid:api-id/prod/*/dashboard/*` in order to give each user access to `/dashboard/user/{username}` will give them access to other routes such as `/admin/dashboard/createAdmin` for example.
|
|
|
|
{% hint style="warning" %}
|
|
Note that **"\*" doesn't stop expanding with slashes**, therefore, if you use "\*" in api-id for example, it could also indicate "any stage" or "any method" as long as the final regex is still valid.\
|
|
So `arn:aws:execute-apis:sa-east-1:accid:*/prod/GET/dashboard/*`\
|
|
Can validate a post request to test stage to the path `/prod/GET/dashboard/admin` for example.
|
|
{% endhint %}
|
|
|
|
You should always have clear what you want to allow to access and then check if other scenarios are possible with the permissions granted.
|
|
|
|
For more info, apart of the [**docs**](https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-control-access-using-iam-policies-to-invoke-api.html), you can find code to implement authorizers in [**this official aws github**](https://github.com/awslabs/aws-apigateway-lambda-authorizer-blueprints/tree/master/blueprints).
|
|
|
|
### IAM Policy Injection
|
|
|
|
In the same [**talk** ](https://www.youtube.com/watch?v=bsPKk7WDOnE)it's exposed the fact that if the code is using **user input** to **generate the IAM policies**, wildcards (and others such as "." or specific strings) can be included in there with the goal of **bypassing restrictions**.
|
|
|
|
### Public URL template
|
|
|
|
```
|
|
https://{random_id}.execute-api.{region}.amazonaws.com/{user_provided}
|
|
```
|
|
|
|
### Get Account ID from public API Gateway URL
|
|
|
|
Just like with S3 buckets, Data Exchange and Lambda URLs gateways, It's possible to find the account ID of an account abusing the **`aws:ResourceAccount`** **Policy Condition Key** from a public API Gateway URL. This is done by finding the account ID one character at a time abusing wildcards in the **`aws:ResourceAccount`** section of the policy.\
|
|
This technique also allows to get **values of tags** if you know the tag key (there some default interesting ones).
|
|
|
|
You can find more information in the [**original research**](https://blog.plerion.com/conditional-love-for-aws-metadata-enumeration/) and the tool [**conditional-love**](https://github.com/plerionhq/conditional-love/) to automate this exploitation.
|
|
|
|
{% hint style="success" %}
|
|
Learn & practice AWS Hacking:<img src="../../../.gitbook/assets/image (1) (1) (1) (1).png" alt="" data-size="line">[**HackTricks Training AWS Red Team Expert (ARTE)**](https://training.hacktricks.xyz/courses/arte)<img src="../../../.gitbook/assets/image (1) (1) (1) (1).png" alt="" data-size="line">\
|
|
Learn & practice GCP Hacking: <img src="../../../.gitbook/assets/image (2) (1).png" alt="" data-size="line">[**HackTricks Training GCP Red Team Expert (GRTE)**<img src="../../../.gitbook/assets/image (2) (1).png" alt="" data-size="line">](https://training.hacktricks.xyz/courses/grte)
|
|
|
|
<details>
|
|
|
|
<summary>Support HackTricks</summary>
|
|
|
|
* Check the [**subscription plans**](https://github.com/sponsors/carlospolop)!
|
|
* **Join the** 💬 [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** us on **Twitter** 🐦 [**@hacktricks\_live**](https://twitter.com/hacktricks_live)**.**
|
|
* **Share hacking tricks by submitting PRs to the** [**HackTricks**](https://github.com/carlospolop/hacktricks) and [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repos.
|
|
|
|
</details>
|
|
{% endhint %}
|