AutoCheck

Msf::Exploit::Remote::AutoCheck automatically runs check before exploit or run. Use prepend, not include. Its implementation is lib/msf/core/exploit/remote/auto_check.rb.

Adding it

class MetasploitModule < Msf::Exploit::Remote
  prepend Msf::Exploit::Remote::AutoCheck
  include Msf::Exploit::Remote::HttpClient

  def check
    CheckCode::Appears('service detected')
  end

  def exploit
    # AutoCheck calls check first
  end
end

Using include causes an explicit failure.

Behavior

1. When AutoCheck is true (the default), run check.
2. Vulnerable / Appears → Continue; call report_vuln if needed.
3. Detected → Warn, then continue.
4. Safe and similar results → Fail. Set ForceExploit true to proceed anyway.

Options

Option	Meaning
AutoCheck	Whether to run check automatically
ForceExploit	Run despite the check result

set AutoCheck false
set ForceExploit true

Writing cautions

• Return a CheckCode from check rather than using fail_with.
• Avoid overly destructive checks; do not prove Vulnerable through a denial of service.
• Use check_host in scanners.

Related: Entry Methods