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|
---
stage: Secure
group: Fuzz Testing
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/#designated-technical-writers
type: reference, howto
---
# Web API Fuzz Testing **(ULTIMATE)**
You can add web API fuzzing to your [GitLab CI/CD](../../../ci/README.md)
pipelines. This helps you discover bugs and potential security issues that other QA processes may miss.
API fuzzing performs fuzz testing of API operation parameters.
Fuzz testing sets operation parameters to unexpected values in an effort to cause unexpected behavior and errors in the API backend.
We recommend that you use fuzz 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/README.md),
you can run fuzz tests as part your CI/CD workflow.
## Requirements
- One of the following web API types:
- REST API
- SOAP
- GraphQL
- Form bodies, JSON, or XML
- An OpenAPI definition, or HTTP Archive (HAR) of requests to test
## When fuzzing scans run
When using the `API-Fuzzing.gitlab-ci.yml` template, the `fuzz` job runs last, as shown here. To
ensure API fuzzing scans the latest code, your CI pipeline should deploy changes to a test
environment in one of the jobs preceding the `fuzz` job:
```yaml
stages:
- build
- test
- deploy
- fuzz
```
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 fuzzing scan. The only changes to the API should be from the fuzzing 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.
## Configuration
There are two ways to perform scans. See the configuration section for the one you wish to use:
- [OpenAPI v2 specification](#openapi-specification)
- [HTTP Archive (HAR)](#http-archive-har)
Examples of both configurations can be found here:
- [Example OpenAPI v2 specification project](https://gitlab.com/gitlab-org/security-products/demos/api-fuzzing-example/-/tree/openapi)
- [Example HTTP Archive (HAR) project](https://gitlab.com/gitlab-org/security-products/demos/api-fuzzing-example/-/tree/har)
### OpenAPI Specification
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 by using
an OpenAPI specification to provide information about the target API to test. OpenAPI specifications
are provided as a filesystem resource or URL.
Follow these steps to configure API fuzzing in GitLab with an OpenAPI specification:
1. To use API fuzzing, you must [include](../../../ci/yaml/README.md#includetemplate)
the [`API-Fuzzing.gitlab-ci.yml` template](https://gitlab.com/gitlab-org/gitlab/blob/master/lib/gitlab/ci/templates/Security/API-Fuzzing.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
include:
- template: API-Fuzzing.gitlab-ci.yml
```
1. Add the configuration file [`gitlab-api-fuzzing-config.yml`](https://gitlab.com/gitlab-org/security-products/analyzers/api-fuzzing/-/blob/master/gitlab-api-fuzzing-config.yml) to your repository's root as `.gitlab-api-fuzzing.yml`.
1. The [configuration file](#configuration-files) has several testing profiles defined with varying
amounts of fuzzing. We recommend that you start with the `Quick-10` profile. Testing with this
profile completes quickly, allowing for easier configuration validation.
Provide the profile by adding the `FUZZAPI_PROFILE` variable to your `.gitlab-ci.yml` file,
substituting `Quick-10` for the profile you choose:
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick-10
```
1. Provide the location of the OpenAPI v2 specification. You can provide the specification as a file
or URL. Specify the location by adding the `FUZZAPI_OPENAPI` variable:
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick-10
FUZZAPI_OPENAPI: test-api-specification.json
```
1. The target API instance's base URL is also required. Provide it by using the `FUZZAPI_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 API fuzzing against an app dynamically created during a GitLab CI/CD
pipeline, have the app persist its domain in an `environment_url.txt` file. API fuzzing
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 `FUZZAPI_TARGET_URL`:
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick-10
FUZZAPI_OPENAPI: test-api-specification.json
FUZZAPI_TARGET_URL: http://test-deployment/
```
This is a minimal configuration for API Fuzzing. From here you can:
- [Run your first scan](#running-your-first-scan).
- [Add authentication](#authentication).
- Learn how to [handle false positives](#handling-false-positives).
DANGER: **Danger:**
**NEVER** run fuzz 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 fuzzing 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 GitLab's API fuzzer, HAR
must contain records of calling the web API to test. The API fuzzer extracts all the requests and
uses them to perform testing.
You can use various tools to generate HAR files:
- [Fiddler](https://www.telerik.com/fiddler): Web debugging proxy
- [Insomnia Core](https://insomnia.rest/): API client
- [Chrome](https://www.google.com/chrome): Browser
- [Firefox](https://www.mozilla.org/en-US/firefox/): Browser
DANGER: **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 API fuzzing to use a HAR file that provides information about the
target API to test:
1. To use API fuzzing, you must [include](../../../ci/yaml/README.md#includetemplate)
the [`API-Fuzzing.gitlab-ci.yml` template](https://gitlab.com/gitlab-org/gitlab/blob/master/lib/gitlab/ci/templates/Security/API-Fuzzing.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
include:
- template: API-Fuzzing.gitlab-ci.yml
```
1. Add the configuration file [`gitlab-api-fuzzing-config.yml`](https://gitlab.com/gitlab-org/security-products/analyzers/api-fuzzing/-/blob/master/gitlab-api-fuzzing-config.yml) to your repository's root as `.gitlab-api-fuzzing.yml`.
1. The [configuration file](#configuration-files) has several testing profiles defined with varying
amounts of fuzzing. We recommend that you start with the `Quick-10` profile. Testing with this
profile completes quickly, allowing for easier configuration validation.
Provide the profile by adding the `FUZZAPI_PROFILE` variable to your `.gitlab-ci.yml` file,
substituting `Quick-10` for the profile you choose:
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick-10
```
1. Add the `FUZZAPI_HAR` variable and set it to the HAR file's location:
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick-10
FUZZAPI_HAR: test-api-specification.json
```
1. The target API instance's base URL is also required. Provide it by using the `FUZZAPI_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 API fuzzing against an app dynamically created during a GitLab CI/CD
pipeline, have the app persist its domain in an `environment_url.txt` file. API fuzzing
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 `FUZZAPI_TARGET_URL`:
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick-10
FUZZAPI_HAR: test-api-specification.json
FUZZAPI_TARGET_URL: http://test-deployment/
```
This is a minimal configuration for API Fuzzing. From here you can:
- [Run your first scan](#running-your-first-scan).
- [Add authentication](#authentication).
- Learn how to [handle false positives](#handling-false-positives).
DANGER: **Danger:**
**NEVER** run fuzz 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 fuzzing against a test server.
### 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)
works by setting the `Authorization` header with the Base64-encoded username and password. The
resulting header looks like this:
```http
Authorization: Basic dXNlcm5hbWU6cGFzc3dvcmQ=
```
To have API fuzzing include this header during a scan, set an overrides environment variable.
Base64-encode your username and password, separated with a `:` (for example, `username:password`).
On Linux, create a text file with the username and password separated by `:`. Make sure the file has
a single line with no return at the end. Then use the command line tool `base64` to encode it.
```shell
$ base64 ~/test.txt
dXNlcm5hbWU6cGFzc3dvcmQ=
```
The output `dXNlcm5hbWU6cGFzc3dvcmQ=` is the Base64-encoded credentials.
DANGER: **Warning:**
Base64 is **not** encryption. This string can be easily decoded and should not be considered a safe
way to protect or store credentials.
[Next create a CI/CD variable](../../../ci/variables/README.md#create-a-custom-variable-in-the-ui),
for example `TEST_API_BASICAUTH`, with the value
`{"headers":{"Authorization":"Basic dXNlcm5hbWU6cGFzc3dvcmQ="}}` (substitute your Base64-encoded
credential string). You can create CI/CD variables from the GitLab projects page at
**Settings > CI/CD** in the **Variables** section.
Set `FUZZAPI_OVERRIDES_ENV` in your `.gitlab-ci.yml` file:
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick
FUZZAPI_OPENAPI: test-api-specification.json
FUZZAPI_TARGET_URL: http://test-deployment/
FUZZAPI_OVERRIDES_ENV: $TEST_API_BASICAUTH
```
#### 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 API fuzzing, 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 API fuzzing can call to generate the token
##### Token doesn't expire
If the bearer token doesn't expire, you can provide it using the `FUZZAPI_OVERRIDES_ENV` variable.
The `FUZZAPI_OVERRIDES_ENV` content is a JSON snippet that provides headers and cookies that should
be added to outgoing HTTP requests made by API fuzzing.
Create a CI/CD variable, 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.
Set `FUZZAPI_OVERRIDES_ENV` in your `.gitlab-ci.yml` file:
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick-10
FUZZAPI_OPENAPI: test-api-specification.json
FUZZAPI_TARGET_URL: http://test-deployment/
FUZZAPI_OVERRIDES_ENV: $TEST_API_BEARERAUTH
```
To validate that authentication is working, run an API fuzzing test and review the fuzzing logs and
the test API's application logs.
##### Token generated at test-runtime
If the bearer token must be generated, and the resulting token doesn't expire during testing, you
can provide to API fuzzing a file containing the token. This file can be generated by a prior stage
and job, or as part of the API fuzzing job.
API fuzzing 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 API fuzzing through the
`FUZZAPI_OVERRIDES_FILE` variable.
Set `FUZZAPI_OVERRIDES_FILE` in your `.gitlab-ci.yml` file:
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick
FUZZAPI_OPENAPI: test-api-specification.json
FUZZAPI_TARGET_URL: http://test-deployment/
FUZZAPI_OVERRIDES_FILE: output/api-fuzzing-overrides.json
```
To validate that authentication is working, run an API fuzzing test and review the fuzzing 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 API fuzzer 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 variables, each set for correct operation:
- `FUZZAPI_OVERRIDES_FILE`: File generated by the provided command.
- `FUZZAPI_OVERRIDES_CMD`: Command to generate JSON file.
- `FUZZAPI_OVERRIDES_INTERVAL`: Interval in seconds to run command.
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick-10
FUZZAPI_OPENAPI: test-api-specification.json
FUZZAPI_TARGET_URL: http://test-deployment/
FUZZAPI_OVERRIDES_FILE: output/api-fuzzing-overrides.json
FUZZAPI_OVERRIDES_CMD: renew_token.py
FUZZAPI_OVERRIDES_INTERVAL: 300
```
To validate that authentication is working, run an API fuzzing test and review the fuzzing logs and
the test API's application logs.
### Configuration files
To get started quickly, GitLab provides you with the configuration file
[`gitlab-api-fuzzing-config.yml`](https://gitlab.com/gitlab-org/security-products/analyzers/api-fuzzing/-/blob/master/gitlab-api-fuzzing-config.yml).
This file has several testing profiles that perform various amounts of testing. The run time of each
increases as the numbers go up. To use a configuration file, add it to your repository's root as
`.gitlab-api-fuzzing.yml`.
| Profile | Scan Type |
|:---------|:-----------|
|Quick-10 |Fuzzing 10 times per parameter |
|Medium-20 |Fuzzing 20 times per parameter |
|Medium-50 |Fuzzing 50 times per parameter |
|Long-100 |Fuzzing 100 times per parameter |
### Available variables
| Environment variable | Description |
|-----------------------------|--------------------|
| `FUZZAPI_VERSION` |Specify API Fuzzing container version. Defaults to `latest`. |
| `FUZZAPI_TARGET_URL` |Base URL of API testing target. |
|[`FUZZAPI_CONFIG`](#configuration-files)|API Fuzzing configuration file. Defaults to `.gitlab-apifuzzer.yml`. |
|[`FUZZAPI_PROFILE`](#configuration-files)|Configuration profile to use during testing. Defaults to `Quick`. |
| `FUZZAPI_REPORT` |Scan report filename. Defaults to `gl-api_fuzzing-report.xml`. |
|[`FUZZAPI_OPENAPI`](#openapi-specification)|OpenAPI specification file or URL. |
|[`FUZZAPI_HAR`](#http-archive-har)|HTTP Archive (HAR) file. |
|[`FUZZAPI_OVERRIDES_FILE`](#overrides) |Path to a JSON file containing overrides. |
|[`FUZZAPI_OVERRIDES_ENV`](#overrides) |JSON string containing headers to override. |
|[`FUZZAPI_OVERRIDES_CMD`](#overrides) |Overrides command. |
|[`FUZZAPI_OVERRIDES_INTERVAL`](#overrides) |How often to run overrides command in seconds. Defaults to `0` (once). |
<!--|[`FUZZAPI_D_TARGET_IMAGE`](#target-container) |API target docker image |
|[`FUZZAPI_D_TARGET_ENV`](#target-container) |Docker environment options |
|[`FUZZAPI_D_TARGET_VOLUME`](#target-container)|Docker volume options |
|[`FUZZAPI_D_TARGET_PORTS`](#target-container) |Docker port options |
| `FUZZAPI_D_WORKER_IMAGE` |Custom worker docker image |
| `FUZZAPI_D_WORKER_ENV` |Custom worker docker environment options |
| `FUZZAPI_D_WORKER_VOLUME` |Custom worker docker volume options |
| `FUZZAPI_D_WORKER_PORTS` |Custom worker docker port options |
| `FUZZAPI_D_NETWORK` |Name of docker network, defaults to "testing-net"|
| `FUZZAPI_D_PRE_SCRIPT` |Pre script runs after docker login and docker network create, but before starting the scanning image container.|
| `FUZZAPI_D_POST_SCRIPT` |Post script runs after scanning image container is started. This is the place to start your target(s) and kick off scanning when using an advanced configuration.| -->
### Overrides
API Fuzzing provides a method to add or override headers and cookies for all outbound HTTP requests
made. You can use this to inject semver headers, authentication, and so on. The
[authentication section](#authentication) includes examples of using overrides for that purpose.
Overrides uses a JSON document to define the headers and cookies:
```json
{
"headers": {
"header1": "value",
"header2": "value"
},
"cookies": {
"cookie1": "value",
"cookie2": "value"
}
}
```
Example usage for setting a single header:
```json
{
"headers": {
"Authorization": "Bearer dXNlcm5hbWU6cGFzc3dvcmQ="
}
}
```
Example usage for setting both a header and cookie:
```json
{
"headers": {
"Authorization": "Bearer dXNlcm5hbWU6cGFzc3dvcmQ="
},
"cookies": {
"flags": "677"
}
}
```
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 `FUZZAPI_OVERRIDES_FILE` environment variable is set. The path is relative to the job current working directory.
Example `.gitlab-ci.yml`:
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick
FUZZAPI_OPENAPI: test-api-specification.json
FUZZAPI_TARGET_URL: http://test-deployment/
FUZZAPI_OVERRIDES_FILE: output/api-fuzzing-overrides.json
```
#### Using an environment variable
To provide the overrides JSON as an environment variable, use the `FUZZAPI_OVERRIDES_ENV` variable.
This allows you to place the JSON as CI/CD variables that can be masked and protected.
In this example `.gitlab-ci.yml`, the JSON is provided directly:
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick
FUZZAPI_OPENAPI: test-api-specification.json
FUZZAPI_TARGET_URL: http://test-deployment/
FUZZAPI_OVERRIDES_ENV: '{"headers":{"X-API-Version":"2"}}'
```
In this example `.gitlab-ci.yml`, the CI/CD variable `SECRET_OVERRIDES` provides the JSON. This is a
[group or instance level environment variable defined in the UI](../../../ci/variables/README.md#instance-level-cicd-environment-variables):
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick
FUZZAPI_OPENAPI: test-api-specification.json
FUZZAPI_TARGET_URL: http://test-deployment/
FUZZAPI_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 API fuzzer 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 variables, each set for correct operation:
- `FUZZAPI_OVERRIDES_FILE`: File generated by the provided command.
- `FUZZAPI_OVERRIDES_CMD`: Command to generate JSON file.
- `FUZZAPI_OVERRIDES_INTERVAL`: Interval in seconds to run command.
```yaml
include:
- template: API-Fuzzing.gitlab-ci.yml
variables:
FUZZAPI_PROFILE: Quick
FUZZAPI_OPENAPI: test-api-specification.json
FUZZAPI_TARGET_URL: http://test-deployment/
FUZZAPI_OVERRIDES_FILE: output/api-fuzzing-overrides.json
FUZZAPI_OVERRIDES_CMD: renew_token.py
FUZZAPI_OVERRIDES_INTERVAL: 300
```
## Running your first scan
When configured correctly, a CI/CD pipeline contains a `Fuzz` stage and a `apifuzzer_fuzz` job. The
job only fails when an invalid configuration is provided. During normal operation, the job always
succeeds even if faults are identified during fuzz testing.
Faults are displayed on the **Tests** pipeline tab with the suite name **API-Fuzzing**. The **Name**
field on the **Tests** page includes the fuzz-tested operation and parameter. The **Trace** field
contains a writeup of the identified fault. This writeup contains information on what the fuzzer
tested and how it detected something wrong.
To prevent an excessive number of reported faults, the API fuzzing scanner limits the number of
faults it reports to one per parameter.
### Fault Writeup
The faults that API fuzzing finds aren't associated with a specific vulnerability type. They require
investigation to determine what type of issue they are and if they should be fixed. See
[handling false positives](#handling-false-positives) for information about configuration changes
you can make to limit the number of false positives reported.
This table contains a description of fields in an API fuzzing fault writeup.
| Writeup Item | Description |
|:-------------|:------------|
| Operation | The operation tested. |
| Parameter | The field modified. This can be a path segment, header, query string, or body element. |
| Endpoint | The endpoint being tested. |
| Check | Check module producing the test. Checks can be turned on and off. |
| Assert | Assert module that detected a failure. Assertions can be configured and turned on and off. |
| CWE | Fuzzing faults always have the same CWE. |
| OWASP | Fuzzing faults always have the same OWASP ID. |
| Exploitability | Fuzzing faults always have an `unknown` exploitability. |
| Impact | Fuzzing faults always have an `unknown` risk impact. |
| Description | Verbose description of what the check did. Includes the original parameter value and the modified (mutated) value. |
| Detection | Why a failure was detected and reported. This is related to the Assert that was used. |
| Original Request | The original, unmodified HTTP request. Useful when reviewing the actual request to see what changes were made. |
| Actual Request | The request that produced the failure. This request has been modified in some way by the Check logic. |
| Actual Response | The response to the actual request. |
| Recorded Request | An unmodified request. |
| Recorded Response | The response to the unmodified request. You can compare this with the actual request when triaging this fault. |
## Handling False Positives
False positives can be handled in two ways:
- Turn off the Check producing the false positive. This prevents the check from generating any
faults. Example checks are the JSON Fuzzing Check, and Form Body Fuzzing Check.
- Fuzzing checks have several methods of detecting when a fault is identified, called _Asserts_.
Asserts can also be turned off and configured. For example, the API fuzzer 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 fault. This isn't always desired, as some frameworks return 500 errors
often.
### 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, simply 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-10
DefaultProfile: Quick
Routes:
- Route: *Route0
Checks:
- Name: FormBodyFuzzingCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
- Name: GeneralFuzzingCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
- Name: JsonFuzzingCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
- Name: XmlFuzzingCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
```
To turn off the General Fuzzing Check you can remove these lines:
```yaml
- Name: GeneralFuzzingCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
```
This results in the following YAML:
```yaml
- Name: Quick-10
DefaultProfile: Quick
Routes:
- Route: *Route0
Checks:
- Name: FormBodyFuzzingCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
- Name: JsonFuzzingCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
- Name: XmlFuzzingCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
```
### Turn off an Assertion for a Check
Assertions detect faults in tests produced by checks. Many checks support multiple Assertions such
as Log Analysis, Response Analysis, and Status Code. When a fault 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 FormBody Fuzzing Check:
```yaml
Checks:
- Name: FormBodyFuzzingCheck
Configuration:
FuzzingCount: 30
UnicodeFuzzing: true
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 `FormBodyFuzzingCheck` from using `StatusCodeAssertion`:
```yaml
Profiles:
- Name: Quick-10
DefaultProfile: Quick
Routes:
- Route: *Route0
Checks:
- Name: FormBodyFuzzingCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
Assertions:
- Name: LogAnalysisAssertion
- Name: ResponseAnalysisAssertion
- Name: GeneralFuzzingCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
- Name: JsonFuzzingCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
- Name: XmlInjectionCheck
Configuration:
FuzzingCount: 10
UnicodeFuzzing: true
```
<!--
### Target Container
The API Fuzzing template supports launching a docker container containing an API target using docker-in-docker.
TODO
-->
## Glossary
- Assert: Assertions are detection modules used by checks to trigger a fault. 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 JSON Fuzzing Check performs fuzz testing of JSON payloads. The API fuzzer is
comprised of several checks. Checks can be turned on and off in a profile.
- Fault: During fuzzing, a failure identified by an Assert is called a fault. Faults are
investigated to determine if they are a security vulnerability, a non-security issue, or a false
positive. Faults don't have a known vulnerability type until they are investigated. Example
vulnerability types are SQL Injection and Denial of Service.
- 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.
|