DAST failing when logging into the target

Summary

DAST test does not complete successfully when adding the login script. (Works fine without attempting to login)

Steps to reproduce

• Add the dast step to the .gitlab-ci.yml as directed by the setup guide. Added below
• Replace the variables with the required credentials
• Run the pipeline

dast:
  stage: test_security
  image: registry.gitlab.com/gitlab-org/security-products/zaproxy
  variables:
    website: "https://test.com/"
    login_url: "https://test.com/login"
    username: "mytestaddress@test.com"
    password: "123123"
  allow_failure: true
  script:
    - mkdir /zap/wrk/
    - /zap/zap-baseline.py -J gl-dast-report.json -t $website
        --auth-url $login_url
        --auth-username $username
        --auth-password $password
    - cp /zap/wrk/gl-dast-report.json .
  artifacts:
    paths: [gl-dast-report.json]

What is the current bug behavior?

The DAST step fails and throws an error.

What is the expected correct behavior?

The DAST step passing and displaying a list of security vulnerabilities

Relevant logs and/or screenshots

Running with gitlab-runner 11.2.0 (35e8515d)
  on ip-172-31-89-116 379c3d34
Using Docker executor with image registry.gitlab.com/gitlab-org/security-products/zaproxy ...
Pulling docker image registry.gitlab.com/gitlab-org/security-products/zaproxy ...
Using docker image sha256:0e87216511f144e84a006e7c978183be04c418e04a146e8ffade980ca2ee0043 for registry.gitlab.com/gitlab-org/security-products/zaproxy ...
Running on runner-379c3d34-project-37-concurrent-0 via ip-172-31-89-116...
Cloning repository...
Cloning into '/builds/Trint/trint.com/trint-frontend'...
Checking out 1d4b2b4d as feature/add-dast-testing...
Skipping Git submodules setup
$ mkdir /zap/wrk/
$ /zap/zap-baseline.py -J gl-dast-report.json -t $website --auth-url $login_url --auth-username-field $username_field --auth-username $username --auth-password $password
Aug 29, 2018 11:56:00 AM java.util.prefs.FileSystemPreferences$1 run
INFO: Created user preferences directory.
2018-08-29 11:56:22,464 Unexpected error: <class 'selenium.common.exceptions.WebDriverException'>
Traceback (most recent call last):
  File "/zap/zap-baseline.py", line 396, in main
    driver = webdriver.Firefox(profile)
  File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/firefox/webdriver.py", line 162, in __init__
    keep_alive=True)
  File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/remote/webdriver.py", line 154, in __init__
    self.start_session(desired_capabilities, browser_profile)
  File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/remote/webdriver.py", line 243, in start_session
    response = self.execute(Command.NEW_SESSION, parameters)
  File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/remote/webdriver.py", line 312, in execute
    self.error_handler.check_response(response)
  File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/remote/errorhandler.py", line 242, in check_response
    raise exception_class(message, screen, stacktrace)
WebDriverException: Message: Process unexpectedly closed with status: 1

ERROR <class 'selenium.common.exceptions.WebDriverException'>
ERROR: Job failed: exit code 1

Output of checks

This happens on self hosting

Possible fixes

I'm not entirely sure what's causing this issue, or if it's a problem with the zaproxy image? I haven't seen any gitlab issues from others having the same problem.