Class: Arachni::Checks::CodeInjectionPhpInputWrapper

Inherits:
Arachni::Check::Base show all
Defined in:
components/checks/active/code_injection_php_input_wrapper.rb

Overview

See Also:

  • https://www.owasp.org/index.php/Top_10_2007-Malicious_File_Execution

Author:

Constant Summary

Constants included from Arachni::Check::Auditor

Arachni::Check::Auditor::DOM_ELEMENTS_WITH_INPUTS, Arachni::Check::Auditor::ELEMENTS_WITH_INPUTS, Arachni::Check::Auditor::FILE_SIGNATURES, Arachni::Check::Auditor::FILE_SIGNATURES_PER_PLATFORM, Arachni::Check::Auditor::Format, Arachni::Check::Auditor::SOURCE_CODE_SIGNATURES_PER_PLATFORM

Constants included from Arachni

BANNER, Arachni::Cookie, Form, Header, JSON, Link, LinkTemplate, NestedCookie, Severity, UIForm, UIInput, VERSION, WEBSITE, WIKI, XML

Instance Attribute Summary

Attributes included from Arachni::Check::Auditor

#framework, #page

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Arachni::Check::Base

#browser_cluster, #clean_up, elements, exempt_platforms, has_exempt_platforms?, has_platforms?, #initialize, platforms, #plugins, prefer, #preferred, preferred, #prepare, #session, supports_platforms?

Methods included from Arachni::Check::Auditor

#audit, #audit_differential, #audit_signature, #audit_timeout, #audited, #audited?, #buffered_audit, #each_candidate_dom_element, #each_candidate_element, has_timeout_candidates?, #http, #initialize, #log, #log_issue, #log_remote_file, #log_remote_file_if_exists, #match_and_log, #max_issues, #preferred, reset, #skip?, timeout_audit_run, #trace_taint, #with_browser, #with_browser_cluster

Methods inherited from Arachni::Component::Base

author, description, fullname, #shortname, shortname, shortname=, version

Methods included from Arachni::Component::Output

#depersonalize_output, #depersonalize_output?, #intercept_print_message

Methods included from UI::Output

#caller_location, #debug?, #debug_level, #debug_level_1?, #debug_level_2?, #debug_level_3?, #debug_level_4?, #debug_off, #debug_on, #disable_only_positives, #error_buffer, #error_log_fd, #error_logfile, #has_error_log?, #included, #log_error, #mute, #muted?, #only_positives, #only_positives?, #print_bad, #print_debug, #print_debug_backtrace, #print_debug_exception, #print_debug_level_1, #print_debug_level_2, #print_debug_level_3, #print_debug_level_4, #print_error, #print_error_backtrace, #print_exception, #print_info, #print_line, #print_ok, #print_status, #print_verbose, #reroute_to_file, #reroute_to_file?, reset_output_options, #set_error_logfile, #unmute, #verbose?, #verbose_off, #verbose_on

Methods included from Arachni::Component::Utilities

#read_file

Methods included from Utilities

#available_port, available_port_mutex, #bytes_to_kilobytes, #bytes_to_megabytes, #caller_name, #caller_path, #cookie_decode, #cookie_encode, #cookies_from_file, #cookies_from_parser, #cookies_from_response, #exception_jail, #exclude_path?, #follow_protocol?, #form_decode, #form_encode, #forms_from_parser, #forms_from_response, #full_and_absolute_url?, #generate_token, #get_path, #hms_to_seconds, #html_decode, #html_encode, #include_path?, #links_from_parser, #links_from_response, #normalize_url, #page_from_response, #page_from_url, #parse_set_cookie, #path_in_domain?, #path_too_deep?, #port_available?, #rand_port, #random_seed, #redundant_path?, #regexp_array_match, #remove_constants, #request_parse_body, #seconds_to_hms, #skip_page?, #skip_path?, #skip_resource?, #skip_response?, #to_absolute, #uri_decode, #uri_encode, #uri_parse, #uri_parse_query, #uri_parser, #uri_rewrite

Methods included from Arachni

URI, collect_young_objects, #get_long_win32_filename, jruby?, null_device, profile?, windows?

Constructor Details

This class inherits a constructor from Arachni::Check::Base

Class Method Details

.infoObject



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# File 'components/checks/active/code_injection_php_input_wrapper.rb', line 46

def self.info
    {
        name:        'Code injection (php://input wrapper)',
        description: %q{
Injects PHP code into the HTTP request body and uses the `php://input` wrapper
to try and load it.
},
        elements:    [ Element::Form, Element::Link, Element::Cookie, Element::Header ],
        author:      'Tasos "Zapotek" Laskos <[email protected]> ',
        version:     '0.1.3',
        platforms:   [:php],

        issue:       {
            name:        %q{Code injection (php://input wrapper)},
            description:     %q{
A modern web application will be reliant on several different programming languages.

These languages can be broken up in two flavours. These are client-side languages
(such as those that run in the browser -- like JavaScript) and server-side
languages (which are executed by the server -- like ASP, PHP, JSP, etc.) to form
the dynamic pages (client-side code) that are then sent to the client.

Because all server-side code should be executed by the server, it should only ever
come from a trusted source.

Code injection occurs when the server takes untrusted code (ie. from the client)
and executes it.

Cyber-criminals will abuse this weakness to execute arbitrary code on the server,
which could result in complete server compromise.

Arachni was able to inject specific server-side code via a PHP wrapper (`php://input`)
and have the executed output from the code contained within the server response.
This indicates that proper input sanitisation is not occurring.
},
            references:  {
                'OWASP' => 'https://www.owasp.org/index.php/Top_10_2007-Malicious_File_Execution'
            },
            tags:        %w(remote injection php code execution),
            cwe:         94,
            severity:    Severity::HIGH,
            remedy_guidance: %q{
It is recommended that untrusted input is never processed as server-side code.

To validate input, the application should ensure that the supplied value contains
only the data that are required to perform the relevant action.

For example, where a username is required, then no non-alpha characters should not
be accepted.
}
        }
    }
end

.optionsObject



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# File 'components/checks/active/code_injection_php_input_wrapper.rb', line 13

def self.options
    @options ||= {
        format:     [Format::STRAIGHT],
        body:       "<?php echo 'vDBVBsbVdv'; ?> <?php echo chr(80).chr(76).chr(76).chr(33).chr(56).chr(111).chr(55) ?>",
        signatures: 'vDBVBsbVdv PLL!8o7',

        # Add one more mutation (on the fly) which will include the extension
        # of the original value (if that value was a filename) after a null byte.
        each_mutation: proc do |mutation|
            next if !mutation.affected_input_value

            # Don't bother if the current element type can't carry nulls.
            next if !mutation.valid_input_value_data?( "\0" )

            m = mutation.dup

            # Figure out the extension of the default value, if it has one.
            ext = m.default_inputs[m.affected_input_name].to_s.split( '.' )
            ext = ext.size > 1 ? ext.last : nil

            # Null-terminate the injected value and append the ext.
            m.affected_input_value += "\0.#{ext}"

            # Pass our new element back to be audited.
            m
        end
    }
end

Instance Method Details

#runObject



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# File 'components/checks/active/code_injection_php_input_wrapper.rb', line 42

def run
    audit 'php://input', self.class.options
end