Module: Arachni::Check::Auditor

Included in:
Base
Defined in:
lib/arachni/check/auditor.rb

Overview

Included by Base and provides helper audit methods to all checks.

There are 3 main types of audit and analysis techniques available:

It should be noted that actual analysis takes place at the element level, and to be more specific, the Element::Capabilities::Auditable element level.

It also provides:

Author:

Constant Summary collapse

Format =

Holds constant bitfields that describe the preferred formatting of injection strings.

Element::Capabilities::Mutable::Format
ELEMENTS_WITH_INPUTS =

Non-DOM auditable elements.

[
    Element::Link, Element::Form, Element::Cookie, Element::Header,
    Element::LinkTemplate, Element::JSON, Element::XML
]
DOM_ELEMENTS_WITH_INPUTS =

Auditable DOM elements.

[
    Element::Link::DOM, Element::Form::DOM, Element::Cookie::DOM,
    Element::LinkTemplate::DOM
]
OPTIONS =

Default audit options.

{

    # Elements to audit.
    #
    # If no elements have been passed to audit methods, candidates will be
    # determined by {#each_candidate_element}.
    elements:     ELEMENTS_WITH_INPUTS,

    dom_elements: DOM_ELEMENTS_WITH_INPUTS,

    # If set to `true` the HTTP response will be analyzed for new elements.
    # Be careful when enabling it, there'll be a performance penalty.
    #
    # If set to `false`, no training is going to occur.
    #
    # If set to `nil`, when the Auditor submits a form with original or
    # sample values this option will be overridden to `true`
    train:        nil
}

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#framework ⇒ Arachni::Framework (readonly)

Returns:



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# File 'lib/arachni/check/auditor.rb', line 221

def framework
  @framework
end

#page ⇒ Arachni::Page (readonly)

Returns Page object to be audited.

Returns:



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# File 'lib/arachni/check/auditor.rb', line 218

def page
  @page
end

Class Method Details

.has_timeout_candidates? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arachni/check/auditor.rb', line 45

def self.has_timeout_candidates?
    Element::Capabilities::Analyzable.has_timeout_candidates?
end

.included(m) ⇒ Object 



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# File 'lib/arachni/check/auditor.rb', line 71

def self.included( m )
    m.class_eval do

        # Determines whether or not to run the check against the given page
        # depending on which elements exist in the page, which elements the
        # check is configured to audit and user options.
        #
        # @param    [Page]    page
        # @param    [Element::Base, Array<Element::Base>]    restrict_to_elements
        #   Element types to check for.
        #
        # @return   [Bool]
        def self.check?( page, restrict_to_elements = nil, ignore_dom_depth = false )
            return false if issue_limit_reached?
            return true  if elements.empty?

            audit                = Arachni::Options.audit
            restrict_to_elements = [restrict_to_elements].flatten.compact

            # We use procs to make the decisions to avoid loading the page
            # element caches unless it's absolutely necessary.
            #
            # Also, it's better to audit Form & Cookie DOM elements only
            # after the page has gone through the browser, because then
            # we'll have some context in the metadata which can help us
            # optimize DOM audits.
            {
                Element::Link              =>
                    proc { audit.links?     && !!page.links.find { |e| e.inputs.any? } },
                Element::Link::DOM         =>
                    proc { audit.link_doms? && !!page.links.find(&:dom) },
                Element::Form              =>
                    proc { audit.forms? && !!page.forms.find { |e| e.inputs.any? } },
                Element::Form::DOM         =>
                    proc { (ignore_dom_depth || page.dom.depth > 0) &&
                        audit.form_doms? && page.has_script? && !!page.forms.find(&:dom) },
                Element::Cookie            =>
                    proc { audit.cookies? && page.cookies.any? },
                Element::Cookie::DOM       =>
                    proc { (ignore_dom_depth || page.dom.depth > 0) &&
                        audit.cookie_doms? && page.has_script? && page.cookies.any? },
                Element::Header            =>
                    proc { audit.headers? && page.headers.any? },
                Element::LinkTemplate      =>
                    proc { audit.link_templates? && page.link_templates.find { |e| e.inputs.any? } },
                Element::LinkTemplate::DOM =>
                    proc { audit.link_template_doms? && !!page.link_templates.find(&:dom) },
                Element::JSON              =>
                    proc { audit.jsons? && page.jsons.find { |e| e.inputs.any? } },
                Element::XML               =>
                    proc { audit.xmls? && page.xmls.find { |e| e.inputs.any? } },
                Element::Body              => !page.body.empty?,
                Element::GenericDOM        => page.has_script?,
                Element::Path              => true,
                Element::Server            => true
            }.each do |type, decider|
                next if restrict_to_elements.any? && !restrict_to_elements.include?( type )

                return true if elements.include?( type ) &&
                    (decider.is_a?( Proc ) ? decider.call : decider)
            end

            false
        end

        def self.issue_counter
            @issue_counter ||= 0
        end

        def self.issue_counter=( int )
            @issue_counter = int
        end

        def increment_issue_counter
            self.class.issue_counter += 1
        end

        def issue_limit_reached?( count = max_issues )
            self.class.issue_limit_reached?( count )
        end

        def self.issue_limit_reached?( count = max_issues )
            issue_counter >= count if !count.nil?
        end

        def self.max_issues
            info[:max_issues]
        end

        # Helper method for creating an issue.
        #
        # @param    [Hash]  options
        #   {Issue} options.
        def self.create_issue( options )
            check_info = self.info.dup
            check_info.delete( :issue )
            check_info[:shortname] = self.shortname

            issue_data = self.info[:issue].merge( check: check_info ).merge( options )
            Issue.new( issue_data )
        end
    end
end

.reset ⇒ Object 



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# File 'lib/arachni/check/auditor.rb', line 41

def self.reset
    audited.clear
end

.timeout_audit_run ⇒ Object 



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# File 'lib/arachni/check/auditor.rb', line 48

def self.timeout_audit_run
    Element::Capabilities::Analyzable.timeout_audit_run
end

Instance Method Details

#audit(payloads, opts = {}, &block) ⇒ Object

If a block has been provided it calls Element::Capabilities::Auditable#audit for every element, otherwise, it defaults to #audit_taint.

Uses #each_candidate_element to decide which elements to audit.

See Also:



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# File 'lib/arachni/check/auditor.rb', line 540

def audit( payloads, opts = {}, &block )
    opts = OPTIONS.merge( opts )
    if !block_given?
        audit_taint( payloads, opts )
    else
        each_candidate_element( opts[:elements] ) do |e|
            e.audit( payloads, opts, &block )
            audited( e.coverage_id )
        end
    end
end

#audit_differential(opts = {}, &block) ⇒ Object

Audits elements using differential analysis and automatically logs results.

Uses #each_candidate_element to decide which elements to audit.

See Also:



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# File 'lib/arachni/check/auditor.rb', line 573

def audit_differential( opts = {}, &block )
    opts = OPTIONS.merge( opts )
    each_candidate_element( opts[:elements] ) do |e|
        e.differential_analysis( opts, &block )
        audited( e.coverage_id )
    end
end

#audit_taint(payloads, opts = {}) ⇒ Object

Provides easy access to element auditing using simple taint analysis and automatically logs results.

Uses #each_candidate_element to decide which elements to audit.

See Also:



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# File 'lib/arachni/check/auditor.rb', line 559

def audit_taint( payloads, opts = {} )
    opts = OPTIONS.merge( opts )
    each_candidate_element( opts[:elements] )do |e|
        e.taint_analysis( payloads, opts )
        audited( e.coverage_id )
    end
end

#audit_timeout(payloads, opts = {}) ⇒ Object

Audits elements using timing attacks and automatically logs results.

Uses #each_candidate_element to decide which elements to audit.

See Also:



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# File 'lib/arachni/check/auditor.rb', line 587

def audit_timeout( payloads, opts = {} )
    opts = OPTIONS.merge( opts )
    each_candidate_element( opts[:elements] ) do |e|
        e.timeout_analysis( payloads, opts )
        audited( e.coverage_id )
    end
end

#audited(id) ⇒ Object

Parameters:

  • id (#to_s) —

    Identifier of the object to be marked as audited.

See Also:



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# File 'lib/arachni/check/auditor.rb', line 56

def audited( id )
    Auditor.audited << "#{self.class}-#{id}"
end

#audited?(id) ⇒ Bool

Returns ‘true` if audited, `false` otherwise.

Parameters:

  • id (#to_s) —

    Identifier of the object to be checked.

Returns:

  • (Bool) —

    ‘true` if audited, `false` otherwise.

See Also:



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# File 'lib/arachni/check/auditor.rb', line 67

def audited?( id )
    Auditor.audited.include?( "#{self.class}-#{id}" )
end

#each_candidate_dom_element(types = []) {|element| ... } ⇒ Object

Passes each element prepared for audit to the block.

If no element types have been specified in ‘opts`, it will use the elements from the check’s Base.info hash.

If no elements have been specified in ‘opts` or Base.info, it will use the elements in OPTIONS.

Parameters:

  • types (Array) (defaults to: []) —

    Element types to audit (see OPTIONS‘[:elements]`).

Yields:

  • (element) —

    Each candidate element.

Yield Parameters:



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# File 'lib/arachni/check/auditor.rb', line 504

def each_candidate_dom_element( types = [], &block )
    types = self.class.info[:elements]    if types.empty?
    types = OPTIONS[:dom_elements]        if types.empty?

    types.each do |elem|
        elem = elem.type

        next if !Options.audit.elements?( elem.to_s.gsub( '_dom', '' ) )

        case elem
            when Element::Link::DOM.type
                prepare_each_dom_element( page.links, &block )

            when Element::Form::DOM.type
                prepare_each_dom_element( page.forms, &block )

            when Element::Cookie::DOM.type
                prepare_each_dom_element( page.cookies, &block )

            when Element::LinkTemplate::DOM.type
                prepare_each_dom_element( page.link_templates, &block )

            else
                fail ArgumentError, "Unknown DOM element: #{elem}"
        end
    end
end

#each_candidate_element(types = []) {|element| ... } ⇒ Object

Passes each element prepared for audit to the block.

If no element types have been specified in ‘opts`, it will use the elements from the check’s Base.info hash.

If no elements have been specified in ‘opts` or Base.info, it will use the elements in OPTIONS.

Parameters:

  • types (Array) (defaults to: []) —

    Element types to audit (see OPTIONS‘[:elements]`).

Yields:

  • (element) —

    Each candidate DOM element.

Yield Parameters:

  • (Arachni::Capabilities::Auditable::DOM) 


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# File 'lib/arachni/check/auditor.rb', line 453

def each_candidate_element( types = [], &block )
    types = self.class.info[:elements] if types.empty?
    types = OPTIONS[:elements]         if types.empty?

    types.each do |elem|
        elem = elem.type

        next if !Options.audit.elements?( elem )

        case elem
            when Element::Link.type
                prepare_each_element( page.links, &block )

            when Element::Form.type
                prepare_each_element( page.forms, &block )

            when Element::Cookie.type
                prepare_each_element(page.cookies, &block )

            when Element::Header.type
                prepare_each_element( page.headers, &block )

            when Element::LinkTemplate.type
                prepare_each_element( page.link_templates, &block )

            when Element::JSON.type
                prepare_each_element( page.jsons, &block )

            when Element::XML.type
                prepare_each_element( page.xmls, &block )

            else
                fail ArgumentError, "Unknown element: #{elem}"
        end
    end
end

#http ⇒ HTTP::Client

Returns:



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# File 'lib/arachni/check/auditor.rb', line 231

def http
    HTTP::Client
end

#initialize(page, framework) ⇒ Object

Parameters:



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# File 'lib/arachni/check/auditor.rb', line 225

def initialize( page, framework )
    @page      = page
    @framework = framework
end

#log(options) ⇒ Issue

Populates and logs an Issue.

Parameters:

  • options (Hash) —

    Issue initialization options.

Returns:



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# File 'lib/arachni/check/auditor.rb', line 279

def log( options )
    options       = options.dup
    vector        = options[:vector]
    audit_options = vector.respond_to?( :audit_options ) ?
        vector.audit_options : {}

    if options[:response]
        page = options.delete(:response).to_page
    elsif options[:page]
        page = options.delete(:page)
    else
        page = self.page
    end

    msg = "In #{vector.type}"

    active = vector.respond_to?( :affected_input_name ) && vector.affected_input_name

    if active
        msg << " input '#{vector.affected_input_name}'"
    elsif vector.respond_to?( :inputs )
        msg << " with inputs '#{vector.inputs.keys.join(', ')}'"
    end

    print_ok "#{msg} with action #{vector.action}"

    if verbose?
        if active
            print_verbose "Injected:  #{vector.affected_input_value.inspect}"
        end

        if options[:signature]
            print_verbose "Signature: #{options[:signature]}"
        end

        if options[:proof]
            print_verbose "Proof:     #{options[:proof]}"
        end

        if page.dom.transitions.any?
            print_verbose 'DOM transitions:'
            page.dom.print_transitions( method(:print_verbose), '    ' )
        end

        if !(request_dump = page.request.to_s).empty?
            print_verbose "Request: \n#{request_dump}"
        end

        print_verbose( '---------' ) if only_positives?
    end

    # Platform identification by vulnerability.
    platform_type = nil
    if (platform = (options.delete(:platform) || audit_options[:platform]))
        Platform::Manager[vector.action] << platform if Options.fingerprint?
        platform_type = Platform::Manager[vector.action].find_type( platform )
    end

    log_issue(options.merge(
        platform_name: platform,
        platform_type: platform_type,
        page:          page
    ))
end

#log_issue(options) ⇒ Issue

Helper method for issue logging.

Parameters:

Returns:

See Also:

  • create_issue


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# File 'lib/arachni/check/auditor.rb', line 385

def log_issue( options )
    return if issue_limit_reached?
    self.class.issue_counter += 1

    issue = self.class.create_issue( options.merge( referring_page: self.page ) )
    Data.issues << issue
    issue
end

#log_remote_file(response, silent = false) ⇒ Issue #log_remote_file(page, silent = false) ⇒ Issue Also known as: log_remote_directory

Logs the existence of a remote file as an issue.

Overloads:

  • #log_remote_file(response, silent = false) ⇒ Issue

    Parameters:

    • response (HTTP::Response)
    • silent (Bool) (defaults to: false) —

      If ‘false`, a message will be printed to stdout containing the status of the operation.

  • #log_remote_file(page, silent = false) ⇒ Issue

    Parameters:

    • page (Page)
    • silent (Bool) (defaults to: false) —

      If ‘false`, a message will be printed to stdout containing the status of the operation.

Returns:

See Also:



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# File 'lib/arachni/check/auditor.rb', line 361

def log_remote_file( page_or_response, silent = false )
    page = page_or_response.is_a?( Page ) ?
        page_or_response : page_or_response.to_page

    issue = log_issue(
        vector: Element::Server.new( page.url ),
        proof:  page.response.status_line,
        page:   page
    )

    print_ok( "Found #{page.url}" ) if !silent

    issue
end

#log_remote_file_if_exists(url, silent = false, &block) ⇒ Object Also known as: log_remote_directory_if_exists

Note:

Ignores custom 404 responses.

Logs a remote file or directory if it exists.

Parameters:

  • url (String) —

    Resource to check.

  • silent (Bool) (defaults to: false) —

    If ‘false`, a message will be printed to stdout containing the status of the operation.

  • block (Proc) —

    Called if the file exists, just before logging the issue, and is passed the HTTP response.

Returns:

  • (Object) —

    • ‘nil` if no URL was provided.

    • ‘false` if the request couldn’t be fired.

    • ‘true` if everything went fine.

See Also:



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# File 'lib/arachni/check/auditor.rb', line 253

def log_remote_file_if_exists( url, silent = false, &block )
    @server ||= Element::Server.new( page.url ).tap { |s| s.auditor = self }
    @server.log_remote_file_if_exists( url, silent, &block )
end

#match_and_log(patterns, &block) ⇒ Object

Matches an array of regular expressions against a string and logs the result as an issue.

Parameters:

  • patterns (Array<Regexp>) —

    Array of regular expressions to be tested.

  • block (Block) —

    Block to verify matches before logging, must return ‘true`/`false`.

See Also:



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# File 'lib/arachni/check/auditor.rb', line 268

def match_and_log( patterns, &block )
    @body ||= Element::Body.new( self.page.url ).tap { |b| b.auditor = self }
    @body.match_and_log( patterns, &block )
end

#max_issues ⇒ Object 



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# File 'lib/arachni/check/auditor.rb', line 175

def max_issues
    self.class.max_issues
end

#preferred ⇒ Object

This method is abstract.

See Also:



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# File 'lib/arachni/check/auditor.rb', line 397

def preferred
    []
end

#skip?(element) ⇒ Boolean

This is called right before an Element is audited and is used to determine whether to skip it or not.

Running checks can override this as they wish but at their own peril.

Parameters:

Returns:

  • (Boolean) —

    ‘true` if the element should be skipped, `false` otherwise.

See Also:

  • Page#audit?


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# File 'lib/arachni/check/auditor.rb', line 412

def skip?( element )
    # This method also gets called from Auditable#audit to check mutations,
    # don't touch these, we're filtering at a higher level here, otherwise
    # we might mess up the audit.
    return true if !element.mutation? && audited?( element.coverage_id )
    return true if !page.audit_element?( element )

    # Don't audit elements which have been already logged as vulnerable
    # either by us or preferred checks.
    (preferred | [shortname]).each do |check|
        next if !framework.checks.include?( check )

        klass = framework.checks[check]
        next if !klass.info.include?(:issue)

        # No point in doing the following heavy deduplication check if there
        # are no issues logged to begin with.
        next if klass.issue_counter == 0

        if Data.issues.include?( klass.create_issue( vector: element ) )
            return true
        end
    end

    false
end

#trace_taint(resource, options = {}, &block) ⇒ Object

Traces the taint in the given ‘resource` and passes each page to the `block`.

Parameters:

  • resource (Page, String, HTTP::Response) —

    Resource to load and whose environment to trace, if given a ‘String` it will be treated it as a URL and will be loaded.

  • options (Hash) (defaults to: {}) —

    See BrowserCluster::Jobs::TaintTrace accessors.

  • block (Block) —

    Block to handle each page snapshot. If the ‘block` returns a `true` value, further analysis will be aborted.



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# File 'lib/arachni/check/auditor.rb', line 606

def trace_taint( resource, options = {}, &block )
    with_browser_cluster do |cluster|
        cluster.trace_taint( resource, options ) do |result|
            # Mark the job as done and abort further analysis if the block
            # returns true.
            cluster.job_done( result.job ) if block.call( result.page )
        end
    end
end

#with_browser(&block) ⇒ Object

Note:

Operates in non-blocking mode.

Parameters:

See Also:

  • BrowserCluster::Worker#with_browser


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# File 'lib/arachni/check/auditor.rb', line 630

def with_browser( &block )
    with_browser_cluster { |cluster| cluster.with_browser( &block ) }
    true
end

#with_browser_cluster(&block) ⇒ Object

Parameters:

  • block (Block) —

    Block to passed a BrowserCluster, if one is available.



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# File 'lib/arachni/check/auditor.rb', line 618

def with_browser_cluster( &block )
    return if !browser_cluster
    block.call browser_cluster
    true
end