Class: Arachni::Checks::InsecureCORSPolicy

Inherits:
Arachni::Check::Base show all
Defined in:
components/checks/passive/grep/insecure_cors_policy.rb

Overview

Author:

Version:

  • 0.1.1

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



24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
# File 'components/checks/passive/grep/insecure_cors_policy.rb', line 24

def self.info
    {
        name:        'Insecure CORS policy',
        description: %q{Checks the host for a wildcard (`*`) `Access-Control-Allow-Origin` header.},
        author:      'Tasos Laskos <[email protected]>',
        version:     '0.1.1',
        elements:    [ Element::Server ],

        issue:       {
            name:        %q{Insecure 'Access-Control-Allow-Origin' header},
            description: %q{
_Cross Origin Resource Sharing (CORS)_ is an HTML5 technology which gives modern
web browsers the ability to bypass restrictions implemented by the _Same Origin Policy_.
The _Same Origin Policy_ requires that both the JavaScript and the page are loaded
from the same domain in order to allow JavaScript to interact with the page. This
in turn prevents malicious JavaScript being executed when loaded from external domains.

The CORS policy allows the application to specify exceptions to the protections
implemented by the browser, and allows the developer to whitelist domains for
which external JavaScript is permitted to execute and interact with the page.

A weak CORS policy is one which whitelists all domains using a wildcard (`*`),
which will allow any externally loaded JavaScript resource to interact with the
affected page. This can severely increase the risk of attacks such as Cross Site Scripting etc.

Arachni detected that the CORS policy being set by the server was weak, and used
a wildcard value. This is evident by the `Access-Control-Allow-Origin` header being set to `*`.
},
            references:  {
                'OWASP' => 'https://www.owasp.org/index.php/CORS_OriginHeaderScrutiny',
                'Mozilla Developer Network' => 'https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS'
            },
            severity:    Severity::LOW,
            remedy_guidance: %q{
It is important that weak CORS policies are not used. Policies can be hardened by
removing the wildcard and individually specifying the domains where the trusted
JavaScript resources are located. If the list of hosts for externally hosted
JavaScript resources is excessive, then a whole top level domain can be whitelisted
by using a combination of the wildcard and the domain (example: `*.arachni-scanner.com`).
}
        }
    }
end

Instance Method Details

#runObject



13
14
15
16
17
18
19
20
21
22
# File 'components/checks/passive/grep/insecure_cors_policy.rb', line 13

def run
    return if audited?( page.parsed_url.host ) ||
        page.response.headers['Access-Control-Allow-Origin'] != '*'
    audited( page.parsed_url.host )

    log(
        vector: Element::Server.new( page.url ),
        proof:  page.response.headers_string[/Access-Control-Allow-Origin.*$/i]
    )
end