path: root/doc/user/application_security/dast_api/index.md

---
stage: Secure
group: Dynamic Analysis
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
type: reference, howto
---

# DAST API **(ULTIMATE)**

You can add dynamic application security testing of web APIs to your [GitLab CI/CD](../../../ci/index.md) pipelines.
This helps you discover bugs and potential security issues that other QA processes may miss.

We recommend that you use DAST API testing in addition to [GitLab Secure](../index.md)'s
other security scanners and your own test processes. If you're using [GitLab CI/CD](../../../ci/index.md),
you can run DAST API tests as part your CI/CD workflow.

## Requirements

- One of the following web API types:
  - REST API
  - SOAP
  - GraphQL
  - Form bodies, JSON, or XML
- One of the following assets to provide APIs to test:
  - OpenAPI v2 or v3 API definition
  - Postman Collection v2.0 or v2.1
  - HTTP Archive (HAR) of API requests to test

## When DAST API scans run

When using the `DAST-API.gitlab-ci.yml` template, the defined jobs use the `dast` stage by default. To enable your `.gitlab-ci.yml` file must include the `dast` stage in your `stages` definition. To ensure DAST API scans the latest code, your CI pipeline should deploy changes to a test environment in a stage before the `dast` stage:

```yaml
stages:
  - build
  - test
  - deploy
  - dast
```

Note that if your pipeline is configured to deploy to the same web server on each run, running a
pipeline while another is still running could cause a race condition in which one pipeline
overwrites the code from another. The API to scan should be excluded from changes for the duration
of a DAST API scan. The only changes to the API should be from the DAST API scanner. Be aware that
any changes made to the API (for example, by users, scheduled tasks, database changes, code
changes, other pipelines, or other scanners) during a scan could cause inaccurate results.

## Enable DAST API scanning

There are three ways to perform scans. See the configuration section for the one you wish to use:

- [OpenAPI v2 or v3 specification](#openapi-specification)
- [HTTP Archive (HAR)](#http-archive-har)
- [Postman Collection v2.0 or v2.1](#postman-collection)

Examples of various configurations can be found here:

- [Example OpenAPI v2 specification project](https://gitlab.com/gitlab-org/security-products/demos/api-dast/openapi-example)
- [Example HTTP Archive (HAR) project](https://gitlab.com/gitlab-org/security-products/demos/api-dast/har-example)
- [Example Postman Collection project](https://gitlab.com/gitlab-org/security-products/demos/api-dast/postman-example)
- [Example GraphQL project](https://gitlab.com/gitlab-org/security-products/demos/api-dast/graphql-example)
- [Example SOAP project](https://gitlab.com/gitlab-org/security-products/demos/api-dast/soap-example)

WARNING:
GitLab 14.0 will require that you place DAST API configuration files (for example,
`gitlab-dast-api-config.yml`) in your repository's `.gitlab` directory instead of your
repository's root. You can continue using your existing configuration files as they are, but
starting in GitLab 14.0, GitLab will not check your repository's root for configuration files.

### OpenAPI Specification

> Support for OpenAPI Specification using YAML format was
> [introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/330583) in GitLab 14.0.

The [OpenAPI Specification](https://www.openapis.org/) (formerly the Swagger Specification) is an API description format for REST APIs.
This section shows you how to configure API fuzzing using an OpenAPI Specification to provide information about the target API to test.
OpenAPI Specifications are provided as a file system resource or URL. Both JSON and YAML OpenAPI formats are supported.

DAST API uses an OpenAPI document to generate the request body. When a request body is required,
the body generation is limited to these body types:

- `application/x-www-form-urlencoded`
- `multipart/form-data`
- `application/json`

Follow these steps to configure DAST API in GitLab with an OpenAPI specification:

1. To use DAST API, you must [include](../../../ci/yaml/index.md#includetemplate)
   the [`DAST-API.gitlab-ci.yml` template](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/ci/templates/Security/DAST-API.gitlab-ci.yml)
   that's provided as part of your GitLab installation. Add the following to your
   `.gitlab-ci.yml` file:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml
   ```

1. The [configuration file](#configuration-files) has several testing profiles defined with different checks enabled. We recommend that you start with the `Quick` profile.
   Testing with this profile completes faster, allowing for easier configuration validation.

   Provide the profile by adding the `DAST_API_PROFILE` CI/CD variable to your `.gitlab-ci.yml` file,
   substituting `Quick` for the profile you choose:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml

   variables:
     DAST_API_PROFILE: Quick
   ```

1. Provide the location of the OpenAPI specification. You can provide the specification as a file
   or URL. Specify the location by adding the `DAST_API_OPENAPI` variable:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml

   variables:
     DAST_API_PROFILE: Quick
     DAST_API_OPENAPI: test-api-specification.json
   ```

1. The target API instance's base URL is also required. Provide it by using the `DAST_API_TARGET_URL`
   variable or an `environment_url.txt` file.

   Adding the URL in an `environment_url.txt` file at your project's root is great for testing in
   dynamic environments. To run DAST API against an app dynamically created during a GitLab CI/CD
   pipeline, have the app persist its URL in an `environment_url.txt` file. DAST API
   automatically parses that file to find its scan target. You can see an
   [example of this in our Auto DevOps CI YAML](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/ci/templates/Jobs/Deploy.gitlab-ci.yml).

   Here's an example of using `DAST_API_TARGET_URL`:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml

   variables:
     DAST_API_PROFILE: Quick
     DAST_API_OPENAPI: test-api-specification.json
     DAST_API_TARGET_URL: http://test-deployment/
   ```

This is a minimal configuration for DAST API. From here you can:

- [Run your first scan](#running-your-first-scan).
- [Add authentication](#authentication).
- Learn how to [handle false positives](#handling-false-positives).

WARNING:
**NEVER** run DAST API testing against a production server. Not only can it perform *any* function that the API can, it may also trigger bugs in the API. This includes actions like modifying and deleting data. Only run DAST API scanning against a test server.

### HTTP Archive (HAR)

The [HTTP Archive format (HAR)](http://www.softwareishard.com/blog/har-12-spec/)
is an archive file format for logging HTTP transactions. When used with the GitLab DAST API scanner, HAR must contain records of calling the web API to test. The DAST API scanner extracts all the requests and
uses them to perform testing.

You can use various tools to generate HAR files:

- [Insomnia Core](https://insomnia.rest/): API client
- [Chrome](https://www.google.com/chrome/): Browser
- [Firefox](https://www.mozilla.org/en-US/firefox/): Browser
- [Fiddler](https://www.telerik.com/fiddler): Web debugging proxy
- [GitLab HAR Recorder](https://gitlab.com/gitlab-org/security-products/har-recorder): Command line

WARNING:
HAR files may contain sensitive information such as authentication tokens, API keys, and session
cookies. We recommend that you review the HAR file contents before adding them to a repository.

Follow these steps to configure DAST API to use a HAR file that provides information about the
target API to test:

1. To use DAST API, you must [include](../../../ci/yaml/index.md#includetemplate)
   the [`DAST-API.gitlab-ci.yml` template](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/ci/templates/Security/DAST-API.gitlab-ci.yml)
   that's provided as part of your GitLab installation. To do so, add the following to your
   `.gitlab-ci.yml` file:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml
   ```

1. The [configuration file](#configuration-files) has several testing profiles defined with different checks enabled. We recommend that you start with the `Quick` profile.
   Testing with this profile completes faster, allowing for easier configuration validation.

   Provide the profile by adding the `DAST_API_PROFILE` CI/CD variable to your `.gitlab-ci.yml` file,
   substituting `Quick` for the profile you choose:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml

   variables:
     DAST_API_PROFILE: Quick
   ```

1. Provide the location of the HAR specification. You can provide the specification as a file
   or URL. [URL support was introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/285020) in GitLab 13.10 and later. Specify the location by adding the `DAST_API_HAR` variable:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml

   variables:
     DAST_API_PROFILE: Quick
     DAST_API_HAR: test-api-recording.har
   ```

1. The target API instance's base URL is also required. Provide it by using the `DAST_API_TARGET_URL`
   variable or an `environment_url.txt` file.

   Adding the URL in an `environment_url.txt` file at your project's root is great for testing in
   dynamic environments. To run DAST API against an app dynamically created during a GitLab CI/CD
   pipeline, have the app persist its URL in an `environment_url.txt` file. DAST API
   automatically parses that file to find its scan target. You can see an
   [example of this in our Auto DevOps CI YAML](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/ci/templates/Jobs/Deploy.gitlab-ci.yml).

   Here's an example of using `DAST_API_TARGET_URL`:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml

   variables:
     DAST_API_PROFILE: Quick
     DAST_API_HAR: test-api-recording.har
     DAST_API_TARGET_URL: http://test-deployment/
   ```

This is a minimal configuration for DAST API. From here you can:

- [Run your first scan](#running-your-first-scan).
- [Add authentication](#authentication).
- Learn how to [handle false positives](#handling-false-positives).

WARNING:
**NEVER** run DAST API testing against a production server. Not only can it perform *any* function that
the API can, it may also trigger bugs in the API. This includes actions like modifying and deleting
data. Only run DAST API against a test server.

### Postman Collection

The [Postman API Client](https://www.postman.com/product/api-client/) is a popular tool that
developers and testers use to call various types of APIs. The API definitions
[can be exported as a Postman Collection file](https://learning.postman.com/docs/getting-started/importing-and-exporting-data/#exporting-postman-data)
for use with DAST API. When exporting, make sure to select a supported version of Postman
Collection: v2.0 or v2.1.

When used with the GitLab DAST API scanner, Postman Collections must contain definitions of the web API to
test with valid data. The DAST API scanner extracts all the API definitions and uses them to perform
testing.

WARNING:
Postman Collection files may contain sensitive information such as authentication tokens, API keys,
and session cookies. We recommend that you review the Postman Collection file contents before adding
them to a repository.

Follow these steps to configure DAST API to use a Postman Collection file that provides
information about the target API to test:

1. To use DAST API, you must [include](../../../ci/yaml/index.md#includetemplate)
   the [`DAST-API.gitlab-ci.yml` template](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/ci/templates/Security/DAST-API.gitlab-ci.yml)
   that's provided as part of your GitLab installation. To do so, add the following to your
   `.gitlab-ci.yml` file:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml
   ```

1. The [configuration file](#configuration-files) has several testing profiles defined with different checks enabled. We recommend that you start with the `Quick` profile.
   Testing with this profile completes faster, allowing for easier configuration validation.

   Provide the profile by adding the `DAST_API_PROFILE` CI/CD variable to your `.gitlab-ci.yml` file,
   substituting `Quick` for the profile you choose:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml

   variables:
     DAST_API_PROFILE: Quick
   ```

1. Provide the location of the Postman Collection specification. You can provide the specification as a file or URL. Specify the location by adding the `DAST_API_POSTMAN_COLLECTION` variable:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml

   variables:
     DAST_API_PROFILE: Quick
     DAST_API_POSTMAN_COLLECTION: postman-collection_serviceA.json
   ```

1. The target API instance's base URL is also required. Provide it by using the `DAST_API_TARGET_URL`
   variable or an `environment_url.txt` file.

   Adding the URL in an `environment_url.txt` file at your project's root is great for testing in
   dynamic environments. To run DAST API against an app dynamically created during a GitLab CI/CD
   pipeline, have the app persist its URL in an `environment_url.txt` file. DAST API
   automatically parses that file to find its scan target. You can see an
   [example of this in our Auto DevOps CI YAML](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/ci/templates/Jobs/Deploy.gitlab-ci.yml).

   Here's an example of using `DAST_API_TARGET_URL`:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml

   variables:
     DAST_API_PROFILE: Quick
     DAST_API_POSTMAN_COLLECTION: postman-collection_serviceA.json
     DAST_API_TARGET_URL: http://test-deployment/
   ```

This is a minimal configuration for DAST API. From here you can:

- [Run your first scan](#running-your-first-scan).
- [Add authentication](#authentication).
- Learn how to [handle false positives](#handling-false-positives).

WARNING:
**NEVER** run DAST API testing against a production server. Not only can it perform *any* function that
the API can, it may also trigger bugs in the API. This includes actions like modifying and deleting
data. Only run DAST API against a test server.

#### Postman variables

Postman allows the developer to define placeholders that can be used in different parts of the
requests. These placeholders are called variables, as explained in [Using variables](https://learning.postman.com/docs/sending-requests/variables/).
You can use variables to store and reuse values in your requests and scripts. For example, you can
edit the collection to add variables to the document:

![Edit collection variable tab View](img/dast_api_postman_collection_edit_variable.png)

You can then use the variables in sections such as URL, headers, and others:

![Edit request using variables View](img/dast_api_postman_request_edit.png)

Variables can be defined at different [scopes](https://learning.postman.com/docs/sending-requests/variables/#variable-scopes)
(for example, Global, Collection, Environment, Local, and Data). In this example, they're defined at
the Environment scope:

![Edit environment variables View](img/dast_api_postman_environment_edit_variable.png)

When you export a Postman collection, only Postman collection variables are exported into the
Postman file. For example, Postman does not export environment-scoped variables into the Postman
file.

By default, the DAST API scanner uses the Postman file to resolve Postman variable values. If a JSON file
is set in a GitLab CI environment variable `DAST_API_POSTMAN_COLLECTION_VARIABLES`, then the JSON
file takes precedence to get Postman variable values.

Although Postman can export environment variables into a JSON file, the format is not compatible
with the JSON expected by `DAST_API_POSTMAN_COLLECTION_VARIABLES`.

Here is an example of using `DAST_API_POSTMAN_COLLECTION_VARIABLES`:

```yaml
stages:
  - dast

include:
  - template: DAST-API.gitlab-ci.yml

variables:
  DAST_API_PROFILE: Quick
  DAST_API_POSTMAN_COLLECTION: postman-collection_serviceA.json
  DAST_API_POSTMAN_COLLECTION_VARIABLES: variable-collection-dictionary.json
  DAST_API_TARGET_URL: http://test-deployment/
```

The file `variable-collection-dictionary.json` is a JSON document. This JSON is an object with
key-value pairs for properties. The keys are the variables' names, and the values are the variables'
values. For example:

   ```json
   {
      "base_url": "http://127.0.0.1/",
      "token": "Token 84816165151"
   }
   ```

### Authentication

Authentication is handled by providing the authentication token as a header or cookie. You can
provide a script that performs an authentication flow or calculates the token.

#### HTTP Basic Authentication

[HTTP basic authentication](https://en.wikipedia.org/wiki/Basic_access_authentication)
is an authentication method built in to the HTTP protocol and used in conjunction with
[transport layer security (TLS)](https://en.wikipedia.org/wiki/Transport_Layer_Security).
To use HTTP basic authentication, two CI/CD variables are added to your `.gitlab-ci.yml` file:

- `DAST_API_HTTP_USERNAME`: The username for authentication.
- `DAST_API_HTTP_PASSWORD`: The password for authentication.

For the password, we recommended that you [create a CI/CD variable](../../../ci/variables/index.md#custom-cicd-variables)
(for example, `TEST_API_PASSWORD`) set to the password. You can create CI/CD variables from the
GitLab projects page at **Settings > CI/CD**, in the **Variables** section. Use that variable
as the value for `DAST_API_HTTP_PASSWORD`:

```yaml
stages:
  - dast

include:
  - template: DAST-API.gitlab-ci.yml

variables:
  DAST_API_PROFILE: Quick
  DAST_API_HAR: test-api-recording.har
  DAST_API_TARGET_URL: http://test-deployment/
  DAST_API_HTTP_USERNAME: testuser
  DAST_API_HTTP_PASSWORD: $TEST_API_PASSWORD
```

#### Bearer Tokens

Bearer tokens are used by several different authentication mechanisms, including OAuth2 and JSON Web
Tokens (JWT). Bearer tokens are transmitted using the `Authorization` HTTP header. To use bearer
tokens with DAST API, you need one of the following:

- A token that doesn't expire
- A way to generate a token that lasts the length of testing
- A Python script that DAST API can call to generate the token

##### Token doesn't expire

If the bearer token doesn't expire, use the `DAST_API_OVERRIDES_ENV` variable to provide it. This
variable's content is a JSON snippet that provides headers and cookies to add to DAST API's
outgoing HTTP requests.

Follow these steps to provide the bearer token with `DAST_API_OVERRIDES_ENV`:

1. [Create a CI/CD variable](../../../ci/variables/index.md#custom-cicd-variables),
   for example `TEST_API_BEARERAUTH`, with the value
   `{"headers":{"Authorization":"Bearer dXNlcm5hbWU6cGFzc3dvcmQ="}}` (substitute your token). You
   can create CI/CD variables from the GitLab projects page at **Settings > CI/CD**, in the
   **Variables** section.

1. In your `.gitlab-ci.yml` file, set `DAST_API_OVERRIDES_ENV` to the variable you just created:

   ```yaml
   stages:
     - dast

   include:
     - template: DAST-API.gitlab-ci.yml

   variables:
     DAST_API_PROFILE: Quick
     DAST_API_OPENAPI: test-api-specification.json
     DAST_API_TARGET_URL: http://test-deployment/
     DAST_API_OVERRIDES_ENV: $TEST_API_BEARERAUTH
   ```

1. To validate that authentication is working, run an DAST API test and review the job logs
   and the test API's application logs.

##### Token generated at test runtime

If the bearer token must be generated and doesn't expire during testing, you can provide to DAST API a file containing the token. A prior stage and job, or part of the DAST API job, can
generate this file.

DAST API expects to receive a JSON file with the following structure:

```json
{
  "headers" : {
    "Authorization" : "Bearer dXNlcm5hbWU6cGFzc3dvcmQ="
  }
}
```

This file can be generated by a prior stage and provided to DAST API through the
`DAST_API_OVERRIDES_FILE` CI/CD variable.

Set `DAST_API_OVERRIDES_FILE` in your `.gitlab-ci.yml` file:

```yaml
stages:
  - dast

include:
  - template: DAST-API.gitlab-ci.yml

variables:
  DAST_API_PROFILE: Quick
  DAST_API_OPENAPI: test-api-specification.json
  DAST_API_TARGET_URL: http://test-deployment/
  DAST_API_OVERRIDES_FILE: output/dast-api-overrides.json
```

To validate that authentication is working, run an DAST API test and review the job logs and
the test API's application logs.

##### Token has short expiration

If the bearer token must be generated and expires prior to the scan's completion, you can provide a
program or script for the DAST API scanner to execute on a provided interval. The provided script runs in
an Alpine Linux container that has Python 3 and Bash installed. If the Python script requires
additional packages, it must detect this and install the packages at runtime.

The script must create a JSON file containing the bearer token in a specific format:

```json
{
  "headers" : {
    "Authorization" : "Bearer dXNlcm5hbWU6cGFzc3dvcmQ="
  }
}
```

You must provide three CI/CD variables, each set for correct operation:

- `DAST_API_OVERRIDES_FILE`: JSON file the provided command generates.
- `DAST_API_OVERRIDES_CMD`: Command that generates the JSON file.
- `DAST_API_OVERRIDES_INTERVAL`: Interval (in seconds) to run command.

For example:

```yaml
stages:
  - dast

include:
  - template: DAST-API.gitlab-ci.yml

variables:
  DAST_API_PROFILE: Quick
  DAST_API_OPENAPI: test-api-specification.json
  DAST_API_TARGET_URL: http://test-deployment/
  DAST_API_OVERRIDES_FILE: output/dast-api-overrides.json
  DAST_API_OVERRIDES_CMD: renew_token.py
  DAST_API_OVERRIDES_INTERVAL: 300
```

To validate that authentication is working, run an DAST API test and review the job logs and
the test API's application logs.

### Configuration files

To get you started quickly, GitLab provides the configuration file
[`gitlab-dast-api-config.yml`](https://gitlab.com/gitlab-org/security-products/analyzers/dast/-/blob/master/config/gitlab-dast-api-config.yml).
This file has several testing profiles that perform various numbers of tests. The run time of each
profile increases as the test numbers go up. To use a configuration file, add it to your
repository's root as `.gitlab/gitlab-dast-api-config.yml`.

#### Profiles

The following profiles are pre-defined in the default configuration file. Profiles
can be added, removed, and modified by creating a custom configuration.

##### Quick

- Application Information Check
- Cleartext Authentication Check
- FrameworkDebugModeCheck
- HTML Injection Check
- Insecure Http Methods Check
- JSON Hijacking Check
- JSON Injection Check
- Sensitive Information Check
- Session Cookie Check
- SQL Injection Check
- Token Check
- XML Injection Check

##### Full

- Application Information Check
- Cleartext AuthenticationCheck
- CORS Check
- DNS Rebinding Check
- Framework Debug Mode Check
- HTML Injection Check
- Insecure Http Methods Check
- JSON Hijacking Check
- JSON Injection Check
- Open Redirect Check
- Sensitive File Check
- Sensitive Information Check
- Session Cookie Check
- SQL Injection Check
- TLS Configuration Check
- Token Check
- XML Injection Check

### Available CI/CD variables

| CI/CD variable                                       | Description        |
|------------------------------------------------------|--------------------|
| `DAST_API_VERSION`                                    | Specify DAST API container version. Defaults to `latest`. |
| `DAST_API_TARGET_URL`                                 | Base URL of API testing target. |
|[`DAST_API_CONFIG`](#configuration-files)              | DAST API configuration file. Defaults to `.gitlab-dast-api.yml`. |
|[`DAST_API_PROFILE`](#configuration-files)             | Configuration profile to use during testing. Defaults to `Quick`. |
|[`FUZZAPI_EXCLUDE_PATHS`](#exclude-paths)              | Exclude API URL paths from testing. |
|[`DAST_API_OPENAPI`](#openapi-specification)           | OpenAPI specification file or URL. |
|[`DAST_API_HAR`](#http-archive-har)                    | HTTP Archive (HAR) file. |
|[`DAST_API_POSTMAN_COLLECTION`](#postman-collection)   | Postman Collection file. |
|[`DAST_API_POSTMAN_COLLECTION_VARIABLES`](#postman-variables) | Path to a JSON file to extract postman variable values. |
|[`DAST_API_OVERRIDES_FILE`](#overrides)                | Path to a JSON file containing overrides. |
|[`DAST_API_OVERRIDES_ENV`](#overrides)                 | JSON string containing headers to override. |
|[`DAST_API_OVERRIDES_CMD`](#overrides)                 | Overrides command. |
|[`DAST_API_OVERRIDES_INTERVAL`](#overrides)            | How often to run overrides command in seconds. Defaults to `0` (once). |
|[`DAST_API_HTTP_USERNAME`](#http-basic-authentication) | Username for HTTP authentication. |
|[`DAST_API_HTTP_PASSWORD`](#http-basic-authentication) | Password for HTTP authentication. |
|`DAST_API_SERVICE_START_TIMEOUT`                       | How long to wait for target API to become available in seconds. Default is 300 seconds. |
|`DAST_API_TIMEOUT`                                     | How long to wait for API responses in seconds. Default is 30 seconds. |

### Overrides

DAST API provides a method to add or override specific items in your request, for example:

- Headers
- Cookies
- Query string
- Form data
- JSON nodes
- XML nodes

You can use this to inject semantic version headers, authentication, and so on. The
[authentication section](#authentication) includes examples of using overrides for that purpose.

Overrides use a JSON document, where each type of override is represented by a JSON object:

```json
{
  "headers": {
    "header1": "value",
    "header2": "value"
  },
  "cookies": {
    "cookie1": "value",
    "cookie2": "value"
  },
  "query":      {
    "query-string1": "value",
    "query-string2": "value"
  },
  "body-form":  {
    "form-param1": "value",
    "form-param1": "value",
  },
  "body-json":  {
    "json-path1": "value",
    "json-path2": "value",
  },
  "body-xml" :  {
    "xpath1":    "value",
    "xpath2":    "value",
  }
}
```

Example of setting a single header:

```json
{
  "headers": {
    "Authorization": "Bearer dXNlcm5hbWU6cGFzc3dvcmQ="
  }
}
```

Example of setting both a header and cookie:

```json
{
  "headers": {
    "Authorization": "Bearer dXNlcm5hbWU6cGFzc3dvcmQ="
  },
  "cookies": {
    "flags": "677"
  }
}
```

Example usage for setting a `body-form` override:

```json
{
  "body-form":  {
    "username": "john.doe"
  }
}
```

The override engine uses `body-form` when the request body has only form-data content.

Example usage for setting a `body-json` override:

```json
{
  "body-json":  {
    "$.credentials.access-token": "iddqd!42.$"
  }
}
```

Note that each JSON property name in the object `body-json` is set to a [JSON Path](https://goessner.net/articles/JsonPath/)
expression. The JSON Path expression `$.credentials.access-token` identifies the node to be
overridden with the value `iddqd!42.$`. The override engine uses `body-json` when the request body
has only [JSON](https://www.json.org/json-en.html) content.

For example, if the body is set to the following JSON:

```json
{
    "credentials" : {
        "username" :"john.doe",
        "access-token" : "non-valid-password"
    }
}
```

It is changed to:

```json
{
    "credentials" : {
        "username" :"john.doe",
        "access-token" : "iddqd!42.$"
    }
}
```

Here's an example for setting a `body-xml` override. The first entry overrides an XML attribute and
the second entry overrides an XML element:

```json
{
  "body-xml" :  {
    "/credentials/@isEnabled": "true",
    "/credentials/access-token/text()" : "iddqd!42.$"
  }
}
```

Note that each JSON property name in the object `body-xml` is set to an
[XPath v2](https://www.w3.org/TR/xpath20/)
expression. The XPath expression `/credentials/@isEnabled` identifies the attribute node to override
with the value `true`. The XPath expression `/credentials/access-token/text()` identifies the
element node to override with the value `iddqd!42.$`. The override engine uses `body-xml` when the
request body has only [XML](https://www.w3.org/XML/)
content.

For example, if the body is set to the following XML:

```xml
<credentials isEnabled="false">
  <username>john.doe</username>
  <access-token>non-valid-password</access-token>
</credentials>
```

It is changed to:

```xml
<credentials isEnabled="true">
  <username>john.doe</username>
  <access-token>iddqd!42.$</access-token>
</credentials>
```

You can provide this JSON document as a file or environment variable. You may also provide a command
to generate the JSON document. The command can run at intervals to support values that expire.

#### Using a file

To provide the overrides JSON as a file, the `DAST_API_OVERRIDES_FILE` CI/CD variable is set. The path is relative to the job current working directory.

Here's an example `.gitlab-ci.yml`:

```yaml
stages:
  - dast

include:
  - template: DAST-API.gitlab-ci.yml

variables:
  DAST_API_PROFILE: Quick
  DAST_API_OPENAPI: test-api-specification.json
  DAST_API_TARGET_URL: http://test-deployment/
  DAST_API_OVERRIDES_FILE: output/dast-api-overrides.json
```

#### Using a CI/CD variable

To provide the overrides JSON as a CI/CD variable, use the `DAST_API_OVERRIDES_ENV` variable.
This allows you to place the JSON as variables that can be masked and protected.

In this example `.gitlab-ci.yml`, the `DAST_API_OVERRIDES_ENV` variable is set directly to the JSON:

```yaml
stages:
  - dast

include:
  - template: DAST-API.gitlab-ci.yml

variables:
  DAST_API_PROFILE: Quick
  DAST_API_OPENAPI: test-api-specification.json
  DAST_API_TARGET_URL: http://test-deployment/
  DAST_API_OVERRIDES_ENV: '{"headers":{"X-API-Version":"2"}}'
```

In this example `.gitlab-ci.yml`, the `SECRET_OVERRIDES` variable provides the JSON. This is a
[group or instance level CI/CD variable defined in the UI](../../../ci/variables/index.md#add-a-cicd-variable-to-an-instance):

```yaml
stages:
  - dast

include:
  - template: DAST-API.gitlab-ci.yml

variables:
  DAST_API_PROFILE: Quick
  DAST_API_OPENAPI: test-api-specification.json
  DAST_API_TARGET_URL: http://test-deployment/
  DAST_API_OVERRIDES_ENV: $SECRET_OVERRIDES
```

#### Using a command

If the value must be generated or regenerated on expiration, you can provide a program or script for
the DAST API scanner to execute on a specified interval. The provided script runs in an Alpine Linux
container that has Python 3 and Bash installed. If the Python script requires additional packages,
it must detect this and install the packages at runtime. The script creates the overrides JSON file
as defined above.

You must provide three CI/CD variables, each set for correct operation:

- `DAST_API_OVERRIDES_FILE`: File generated by the provided command.
- `DAST_API_OVERRIDES_CMD`: Command to generate JSON file.
- `DAST_API_OVERRIDES_INTERVAL`: Interval in seconds to run command.

```yaml
stages:
  - dast

include:
  - template: DAST-API.gitlab-ci.yml

variables:
  DAST_API_PROFILE: Quick
  DAST_API_OPENAPI: test-api-specification.json
  DAST_API_TARGET_URL: http://test-deployment/
  DAST_API_OVERRIDES_FILE: output/dast-api-overrides.json
  DAST_API_OVERRIDES_CMD: renew_token.py
  DAST_API_OVERRIDES_INTERVAL: 300
```

### Exclude Paths

> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/211892) in GitLab 14.0.

When testing an API it can be useful to exclude certain paths. For example, you might exclude testing of an authentication service or an older version of the API. To exclude paths, use the `FUZZAPI_EXCLUDE_PATHS` CI/CD variable . This variable is specified in your `.gitlab-ci.yml` file. To exclude multiple paths, separate entries using the `;` character. In the provided paths you can use a single character wildcard `?` and `*` for a multiple character wildcard.

To verify the paths are excluded, review the `Tested Operations` and `Excluded Operations` portion of the job output. You should not see any excluded paths listed under `Tested Operations`.

```plaintext
2021-05-27 21:51:08 [INF] API Security: --[ Tested Operations ]-------------------------
2021-05-27 21:51:08 [INF] API Security: 201 POST http://target:7777/api/users CREATED
2021-05-27 21:51:08 [INF] API Security: ------------------------------------------------
2021-05-27 21:51:08 [INF] API Security: --[ Excluded Operations ]-----------------------
2021-05-27 21:51:08 [INF] API Security: GET http://target:7777/api/messages
2021-05-27 21:51:08 [INF] API Security: POST http://target:7777/api/messages
2021-05-27 21:51:08 [INF] API Security: ------------------------------------------------
```

#### Examples

This example excludes the `/auth` resource. This does not exclude child resources (`/auth/child`).

```yaml
variables:
  DAST_API_EXCLUDE_PATHS=/auth
```

To exclude `/auth`, and child resources (`/auth/child`), we use a wildcard.

```yaml
variables:
  DAST_API_EXCLUDE_PATHS=/auth*
```

To exclude multiple paths we use the `;` character. In this example we exclude `/auth*` and `/v1/*`.

```yaml
variables:
  DAST_API_EXCLUDE_PATHS=/auth*;/v1/*
```

## Running your first scan

When configured correctly, a CI/CD pipeline contains a `dast` stage and an `dast_api` job. The job only fails when an invalid configuration is provided. During normal operation, the job always succeeds even if vulnerabilities are identified during testing.

Vulnerabilities are displayed on the **Security** pipeline tab with the suite name. When testing against the repositories default branch, the DAST API vulnerabilities are also shown on the Security & Compliance's Vulnerability Report page.

To prevent an excessive number of reported vulnerabilities, the DAST API scanner limits the number of vulnerabilities it reports per operation.

## Viewing DAST API vulnerabilities

The DAST API analyzer produces a JSON report that is collected and used
[to populate the vulnerabilities into GitLab vulnerability screens](#view-details-of-a-dast-api-vulnerability).

See [handling false positives](#handling-false-positives) for information about configuration changes you can make to limit the number of false positives reported.

### View details of a DAST API vulnerability

Follow these steps to view details of a vulnerability:

1. You can view vulnerabilities in a project, or a merge request:

   - In a project, go to the project's **{shield}** **Security & Compliance > Vulnerability Report**
     page. This page shows all vulnerabilities from the default branch only.
   - In a merge request, go the merge request's **Security** section and click the **Expand**
     button. DAST API vulnerabilities are available in a section labeled
     **DAST detected N potential vulnerabilities**. Click the title to display the vulnerability
     details.

1. Click the vulnerabilities title to display the details. The table below describes these details.

   | Field               | Description                                                                             |
   |:--------------------|:----------------------------------------------------------------------------------------|
   | Description         | Description of the vulnerability including what was modified.                                   |
   | Project             | Namespace and project in which the vulnerability was detected.                          |
   | Method              | HTTP method used to detect the vulnerability.                                           |
   | URL                 | URL at which the vulnerability was detected.                                            |
   | Request             | The HTTP request that caused the vulnerability.                                                 |
   | Unmodified Response | Response from an unmodified request. This is what a normal working response looks like. |
   | Actual Response     | Response received from test request.                                                  |
   | Evidence            | How we determined a vulnerability occurred.                                                     |
   | Identifiers         | The DAST API check used to find this vulnerability.                                              |
   | Severity            | Severity of the vulnerability.                                              |
   | Scanner Type        | Scanner used to perform testing.                                                        |

### Security Dashboard

The Security Dashboard is a good place to get an overview of all the security vulnerabilities in your groups, projects and
pipelines. For more information, see the [Security Dashboard documentation](../security_dashboard/index.md).

### Interacting with the vulnerabilities

Once a vulnerability is found, you can interact with it. Read more on how to
[address the vulnerabilities](../vulnerabilities/index.md).

## Handling False Positives

False positives can be handled in several ways:

- Dismiss the vulnerability.
- Some checks have several methods of detecting when a vulnerability is identified, called _Assertions_.
  Assertions can also be turned off and configured. For example, the DAST API scanner by default uses HTTP
  status codes to help identify when something is a real issue. If an API returns a 500 error during
  testing, this creates a vulnerability. This isn't always desired, as some frameworks return 500 errors often.
- Turn off the Check producing the false positive. This prevents the check from generating any
  vulnerabilities. Example checks are the SQL Injection Check, and JSON Hijacking Check.

### Turn off a Check

Checks perform testing of a specific type and can be turned on and off for specific configuration
profiles. The provided [configuration files](#configuration-files) define several profiles that you
can use. The profile definition in the configuration file lists all the checks that are active
during a scan. To turn off a specific check, remove it from the profile definition in the
configuration file. The profiles are defined in the `Profiles` section of the configuration file.

Example profile definition:

```yaml
Profiles:
  - Name: Quick
    DefaultProfile: Empty
    Routes:
      - Route: *Route0
        Checks:
          - Name: ApplicationInformationCheck
          - Name: CleartextAuthenticationCheck
          - Name: FrameworkDebugModeCheck
          - Name: HtmlInjectionCheck
          - Name: InsecureHttpMethodsCheck
          - Name: JsonHijackingCheck
          - Name: JsonInjectionCheck
          - Name: SensitiveInformationCheck
          - Name: SessionCookieCheck
          - Name: SqlInjectionCheck
          - Name: TokenCheck
          - Name: XmlInjectionCheck
```

To turn off the JSON Hijacking Check you can remove these lines:

```yaml
          - Name: JsonHijackingCheck
```

This results in the following YAML:

```yaml
- Name: Quick
  DefaultProfile: Empty
  Routes:
    - Route: *Route0
      Checks:
        - Name: ApplicationInformationCheck
        - Name: CleartextAuthenticationCheck
        - Name: FrameworkDebugModeCheck
        - Name: HtmlInjectionCheck
        - Name: InsecureHttpMethodsCheck
        - Name: JsonInjectionCheck
        - Name: SensitiveInformationCheck
        - Name: SessionCookieCheck
        - Name: SqlInjectionCheck
        - Name: TokenCheck
        - Name: XmlInjectionCheck
```

### Turn off an Assertion for a Check

Assertions detect vulnerabilities in tests produced by checks. Many checks support multiple Assertions such as Log Analysis, Response Analysis, and Status Code. When a vulnerability is found, the Assertion used is provided. To identify which Assertions are on by default, see the Checks default configuration in the configuration file. The section is called `Checks`.

This example shows the SQL Injection Check:

```yaml
- Name: SqlInjectionCheck
  Configuration:
    UserInjections: []
  Assertions:
    - Name: LogAnalysisAssertion
    - Name: ResponseAnalysisAssertion
    - Name: StatusCodeAssertion
```

Here you can see three Assertions are on by default. A common source of false positives is
`StatusCodeAssertion`. To turn it off, modify its configuration in the `Profiles` section. This
example provides only the other two Assertions (`LogAnalysisAssertion`,
`ResponseAnalysisAssertion`). This prevents `SqlInjectionCheck` from using `StatusCodeAssertion`:

```yaml
Profiles:
  - Name: Quick
    DefaultProfile: Empty
    Routes:
      - Route: *Route0
        Checks:
          - Name: ApplicationInformationCheck
          - Name: CleartextAuthenticationCheck
          - Name: FrameworkDebugModeCheck
          - Name: HtmlInjectionCheck
          - Name: InsecureHttpMethodsCheck
          - Name: JsonHijackingCheck
          - Name: JsonInjectionCheck
          - Name: SensitiveInformationCheck
          - Name: SessionCookieCheck
          - Name: SqlInjectionCheck
            Assertions:
              - Name: LogAnalysisAssertion
              - Name: ResponseAnalysisAssertion
          - Name: TokenCheck
          - Name: XmlInjectionCheck
```

## Troubleshooting

### Failed to start scanner session (version header not found)

The DAST API engine outputs an error message when it cannot establish a connection with the scanner application component. The error message is shown in the job output window of the `dast_api` job. A common cause of this issue is changing the `DAST_API_API` variable from its default.

**Error message**

- In [GitLab 13.11 and later](https://gitlab.com/gitlab-org/gitlab/-/issues/323939), `Failed to start scanner session (version header not found).`
- In GitLab 13.10 and earlier, `API Security version header not found.  Are you sure that you are connecting to the API Security server?`.

**Solution**

- Remove the `DAST_API_API` variable from the `.gitlab-ci.yml` file. The value will be inherited from the DAST API CI/CD template. We recommend this method instead of manually setting a value.
- If removing the variable is not possible, check to see if this value has changed in the latest version of the [DAST API CI/CD template](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/ci/templates/Security/DAST-API.gitlab-ci.yml). If so, update the value in the `.gitlab-ci.yml` file.

### Application cannot determine the base URL for the target API

The DAST API engine outputs an error message when it cannot determine the target API after inspecting the OpenAPI document. This error message is shown when the target API has not been set in the `.gitlab-ci.yml` file, it is not available in the `environment_url.txt` file, and it could not be computed using the OpenAPI document.

There is a order of precedence in which the DAST API engine tries to get the target API when checking the different sources. First, it will try to use the `DAST_API_TARGET_URL`. If the environment variable has not been set, then the DAST API engine will attempt to use the `environment_url.txt` file. If there is no file `environment_url.txt`, then the DAST API engine will use the OpenAPI document contents and the URL provided in `DAST_API_OPENAPI` (if a URL is provided) to try to compute the target API.

The best-suited solution will depend on whether or not your target API changes for each deployment. In static environments, the target API is the same for each deployment, in this case please refer to the [static environment solution](#static-environment-solution). If the target API changes for each deployment a [dynamic environment solution](#dynamic-environment-solutions) should be applied.

#### Static environment solution

This solution is for pipelines in which the target API URL doesn't change (is static).

**Add environmental variable**

For environments where the target API remains the same, we recommend you specify the target URL by using the `DAST_API_TARGET_URL` environment variable. In your `.gitlab-ci.yml`, add a variable `DAST_API_TARGET_URL`. The variable must be set to the base URL of API testing target. For example:

```yaml
include:
    - template: DAST-API.gitlab-ci.yml

  variables:
    DAST_API_TARGET_URL: http://test-deployment/
    DAST_API_OPENAPI: test-api-specification.json
```

#### Dynamic environment solutions

In a dynamic environment your target API changes for each different deployment. In this case, there is more than one possible solution, we recommend you use the `environment_url.txt` file when dealing with dynamic environments.

**Use environment_url.txt**

To support dynamic environments in which the target API URL changes during each pipeline, DAST API engine supports the use of an `environment_url.txt` file that contains the URL to use. This file is not checked into the repository, instead it's created during the pipeline by the job that deploys the test target and collected as an artifact that can be used by later jobs in the pipeline. The job that creates the `environment_url.txt` file must run before the DAST API engine job.

1. Modify the test target deployment job adding the base URL in an `environment_url.txt` file at the root of your project.
1. Modify the test target deployment job collecting the `environment_url.txt` as an artifact.

Example:

```yaml
deploy-test-target:
  script:
    # Perform deployment steps
    # Create environment_url.txt (example)
    - echo http://${CI_PROJECT_ID}-${CI_ENVIRONMENT_SLUG}.example.org > environment_url.txt

  artifacts:
    paths:
      - environment_url.txt
```

## Glossary

- Assert: Assertions are detection modules used by checks to trigger a vulnerability. Many assertions have
  configurations. A check can use multiple Assertions. For example, Log Analysis, Response Analysis,
  and Status Code are common Assertions used together by checks. Checks with multiple Assertions
  allow them to be turned on and off.
- Check: Performs a specific type of test, or performed a check for a type of vulnerability. For
  example, the SQL Injection Check performs DAST testing for SQL Injection vulnerabilities. The DAST API scanner is comprised of several checks. Checks can be turned on and off in a profile.
- Profile: A configuration file has one or more testing profiles, or sub-configurations. You may
  have a profile for feature branches and another with extra testing for a main branch.