# Cloudflare Security

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In a Cloudflare account there are some **general settings and services** that can be configured. In this page we are going to **analyze the security related settings of each section:**

<figure><img src="../../images/image (117).png" alt=""><figcaption></figcaption></figure>

## Websites

Review each with:

{{#ref}}
cloudflare-domains.md
{{#endref}}

### Domain Registration

- [ ] In **`Transfer Domains`** check that it's not possible to transfer any domain.

Review each with:

{{#ref}}
cloudflare-domains.md
{{#endref}}

## Analytics

_I couldn't find anything to check for a config security review._

## Pages

On each Cloudflare's page:

- [ ] Check for **sensitive information** in the **`Build log`**.
- [ ] Check for **sensitive information** in the **Github repository** assigned to the pages.
- [ ] Check for potential github repo compromise via **workflow command injection** or `pull_request_target` compromise. More info in the [**Github Security page**](../github-security/index.html).
- [ ] Check for **vulnerable functions** in the `/fuctions` directory (if any), check the **redirects** in the `_redirects` file (if any) and **misconfigured headers** in the `_headers` file (if any).
- [ ] Check for **vulnerabilities** in the **web page** via **blackbox** or **whitebox** if you can **access the code**
- [ ] In the details of each page `/<page_id>/pages/view/blocklist/settings/functions`. Check for **sensitive information** in the **`Environment variables`**.
- [ ] In the details page check also the **build command** and **root directory** for **potential injections** to compromise the page.

## **Workers**

On each Cloudflare's worker check:

- [ ] The triggers: What makes the worker trigger? Can a **user send data** that will be **used** by the worker?
- [ ] In the **`Settings`**, check for **`Variables`** containing **sensitive information**
- [ ] Check the **code of the worker** and search for **vulnerabilities** (specially in places where the user can manage the input)
- Check for SSRFs returning the indicated page that you can control
- Check XSSs executing JS inside a svg image
- It is possible that the worker interacts with other internal services. For example, a worker may interact with a R2 bucket storing information in it obtained from the input. In that case, it would be necessary to check what capabilities does the worker have over the R2 bucket and how could it be abused from the user input.

> [!WARNING]
> Note that by default a **Worker is given a URL** such as `<worker-name>.<account>.workers.dev`. The user can set it to a **subdomain** but you can always access it with that **original URL** if you know it.

For a practical abuse of Workers as pass-through proxies (IP rotation, FireProx-style), check:

{{#ref}}
cloudflare-workers-pass-through-proxy-ip-rotation.md
{{#endref}}

## R2

On each R2 bucket check:

- [ ] Configure **CORS Policy**.

## Stream

TODO

## Images

TODO

## Security Center

- [ ] If possible, run a **`Security Insights`** **scan** and an **`Infrastructure`** **scan**, as they will **highlight** interesting information **security** wise.
- [ ] Just **check this information** for security misconfigurations and interesting info

## Turnstile

TODO

## **Zero Trust**

{{#ref}}
cloudflare-zero-trust-network.md
{{#endref}}

## Bulk Redirects

> [!NOTE]
> Unlike [Dynamic Redirects](https://developers.cloudflare.com/rules/url-forwarding/dynamic-redirects/), [**Bulk Redirects**](https://developers.cloudflare.com/rules/url-forwarding/bulk-redirects/) are essentially static — they do **not support any string replacement** operations or regular expressions. However, you can configure URL redirect parameters that affect their URL matching behavior and their runtime behavior.

- [ ] Check that the **expressions** and **requirements** for redirects **make sense**.
- [ ] Check also for **sensitive hidden endpoints** that you contain interesting info.

## Notifications

- [ ] Check the **notifications.** These notifications are recommended for security:
- `Usage Based Billing`
- `HTTP DDoS Attack Alert`
- `Layer 3/4 DDoS Attack Alert`
- `Advanced HTTP DDoS Attack Alert`
- `Advanced Layer 3/4 DDoS Attack Alert`
- `Flow-based Monitoring: Volumetric Attack`
- `Route Leak Detection Alert`
- `Access mTLS Certificate Expiration Alert`
- `SSL for SaaS Custom Hostnames Alert`
- `Universal SSL Alert`
- `Script Monitor New Code Change Detection Alert`
- `Script Monitor New Domain Alert`
- `Script Monitor New Malicious Domain Alert`
- `Script Monitor New Malicious Script Alert`
- `Script Monitor New Malicious URL Alert`
- `Script Monitor New Scripts Alert`
- `Script Monitor New Script Exceeds Max URL Length Alert`
- `Advanced Security Events Alert`
- `Security Events Alert`
- [ ] Check all the **destinations**, as there could be **sensitive info** (basic http auth) in webhook urls. Make also sure webhook urls use **HTTPS**
- [ ] As extra check, you could try to **impersonate a cloudflare notification** to a third party, maybe you can somehow **inject something dangerous**

## Manage Account

- [ ] It's possible to see the **last 4 digits of the credit card**, **expiration** time and **billing address** in **`Billing` -> `Payment info`**.
- [ ] It's possible to see the **plan type** used in the account in **`Billing` -> `Subscriptions`**.
- [ ] In **`Members`** it's possible to see all the members of the account and their **role**. Note that if the plan type isn't Enterprise, only 2 roles exist: Administrator and Super Administrator. But if the used **plan is Enterprise**, [**more roles**](https://developers.cloudflare.com/fundamentals/account-and-billing/account-setup/account-roles/) can be used to follow the least privilege principle.
- Therefore, whenever possible is **recommended** to use the **Enterprise plan**.
- [ ] In Members it's possible to check which **members** has **2FA enabled**. **Every** user should have it enabled.

> [!NOTE]
> Note that fortunately the role **`Administrator`** doesn't give permissions to manage memberships (**cannot escalate privs or invite** new members)

## DDoS Investigation

[Check this part](cloudflare-domains.md#cloudflare-ddos-protection).

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