wpscanteam/wpscan · error · WPScan::Error::BrowserFailed

The browser was closed or failed before SAML authentication

Error message

The browser was closed or failed before SAML authentication could be completed (#{e.class}: #{e.message}).

What it means

WPScan::Error::BrowserFailed raised by the catch-all Ferrum::Error rescue in run_login_session (lib/wpscan/browser_authenticator.rb:41-44). Any Ferrum failure other than a missing binary - browser window closed by the user, dead browser process, CDP connection lost, navigation errors - is translated into this message with the original class and message appended. Note the flow deliberately pokes browser.current_url after your enter keypress to detect a browser that died during login.

Source

Thrown at lib/wpscan/browser_authenticator.rb:42

    end

    # Drives the interactive browser session and returns the resulting cookie jar.
    # Translates Ferrum failures into BrowserFailed with a context-specific message.
    def self.run_login_session(login_url)
      browser = Ferrum::Browser.new(headless: false)

      puts 'SAML authentication needed. Log in via the browser window that just opened, then press enter.'
      browser.goto(login_url)
      gets # Waits for user input

      # Attempt an innocuous command to check if the browser is still responsive
      browser.current_url

      browser.cookies.all
    rescue Ferrum::BinaryNotFoundError, Ferrum::EmptyPathError => e
      raise WPScan::Error::BrowserFailed, chrome_not_found_message(e)
    rescue Ferrum::Error => e
      raise WPScan::Error::BrowserFailed,
            'The browser was closed or failed before SAML authentication could be completed ' \
            "(#{e.class}: #{e.message})."
    ensure
      browser.quit if browser&.process
    end

    def self.chrome_not_found_message(error)
      '--expect-saml requires Chrome or Chromium to be installed and available on PATH ' \
        '(install Chrome / Chromium, or point Ferrum at a binary via BROWSER_PATH). ' \
        "Underlying error: #{error.message}"
    end

    def self.serialize_cookies(cookies)
      cookies.map do |_name, cookie|
        raise WPScan::Error::SAMLAuthenticationFailed if cookie.name.match?(COOKIE_DELIMITERS) ||
                                                         cookie.value.to_s.match?(COOKIE_DELIMITERS)

        "#{cookie.name}=#{cookie.value}"

View on GitHub (pinned to 62c9cef471)

Solutions

1. Keep the Chrome window open until after you have pressed enter in the terminal, then let the code close it
2. Kill stale instances and retry: pkill -f chrome; then re-run wpscan --expect-saml
3. Update the gems (gem update wpscan ferrum) so CDP commands match your installed Chrome version
4. Give the environment enough memory (graphical Chrome needs a few hundred MB) or run on a desktop machine

Example fix

# before
<user closes the Chrome window mid-login, then presses enter>
# => BrowserFailed: The browser was closed or failed before SAML authentication could be completed (Ferrum::DeadBrowserError: Browser is dead)

# after
<leave the Chrome window open, finish login, press enter>
# => cookies captured, scan proceeds

# Cheap liveness preflight: make sure no stale chrome holds locks
system('pkill -f chrome.*remote-debugging') || true

begin
  cookies = WPScan::BrowserAuthenticator.run_login_session(login_url)
rescue WPScan::Error::BrowserFailed => e
  if e.message.include?('closed or failed')
    retry if (attempts += 1) < 2 # browser died; one clean retry after killing leftovers
  end
  raise
end

When it happens

Trigger: User closes the Chrome window before (or right after) pressing enter, causing Ferrum::DeadBrowserError on browser.current_url or browser.cookies.all; Chrome crashing (OOM-killed on small containers); DevTools/CDP protocol mismatch between an outdated ferrum gem and a very new Chrome; browser.goto(login_url) failing on a bad URL.

Common situations: Users closing the 'extra' window thinking it is a popup; CI containers with too little memory for a graphical Chrome; old ferrum versions paired with freshly auto-updated Chrome; zombie chrome processes from a previous failed run holding the profile lock.

Understand the failure class

• Authentication and authorization failures — expired tokens, bad credentials, and missing scopes.

Related errors

• --expect-saml requires Chrome or Chromium to be installed an
• SAML authentication is required to access this resource. Ple
• SAML authentication needs an interactive terminal to wait fo
• The option #{opt.to_long} is required
• One of the following options is required: #{opt.to_long}, --

AI-assisted analysis of wpscanteam/wpscan@62c9cef471 (2026-08-21). Data as JSON: /api/errors/1675773efaf1b102. Report an issue: GitHub.