- Do you work in a **cybersecurity company**? Do you want to see your **company advertised in HackTricks**? or do you want to have access to the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
- **Join the** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** me on **Twitter** [**🐦**](https://github.com/carlospolop/hacktricks/tree/7af18b62b3bdc423e11444677a6a73d4043511e9/\[https:/emojipedia.org/bird/README.md)[**@carlospolopm**](https://twitter.com/carlospolopm)**.**
## Active User Credential Theft via Certificates – PERSIST1
If the user is allowed to request a certificate that allows domain authentication, an attacker could **request** and **steal** it to **maintain****persistence**.
The **`User`** template allows that and comes by **default**. However, it might be disabled. So, [**Certify**](https://github.com/GhostPack/Certify) allows you to find valid certificates to persist:
```
Certify.exe find /clientauth
```
Note that a **certificate can be used for authentication** as that user as long as the certificate is **valid**, **even** if the user **changes** their **password**.
From the **GUI** it's possible to request a certificate with `certmgr.msc` or via the command-line with `certreq.exe`.
Using [**Certify**](https://github.com/GhostPack/Certify) you can run:
To **use that certificate**, one can then **upload** the `.pfx` to a target and **use it with** [**Rubeus**](https://github.com/GhostPack/Rubeus) to **request a TGT** for the enrolled user, for as long as the certificate is valid (default lifetime is 1 year):
Combined with the technique outlined in the [**THEFT5**](certificate-theft.md#ntlm-credential-theft-via-pkinit-theft5) section, an attacker can also persistently **obtain the account’s NTLM hash**, which the attacker could use to authenticate via **pass-the-hash** or **crack** to obtain the **plaintext****password**. \
This is an alternative method of **long-term credential theft** that does **not touch LSASS** and is possible from a **non-elevated context.**
{% endhint %}
## Machine Persistence via Certificates - PERSIST2
If a certificate template allowed for **Domain Computers** as enrolment principals, an attacker could **enrol a compromised system’s machine account**. The default **`Machine`** template matches all those characteristics.
If an **attacker elevates privileges** on compromised system, the attacker can use the **SYSTEM** account to enrol in certificate templates that grant enrolment privileges to machine accounts (more information in [**THEFT3**](certificate-theft.md#machine-certificate-theft-via-dpapi-theft3)).
You can use [**Certify**](https://github.com/GhostPack/Certify) to gather a certificate for the machine account elevating automatically to SYSTEM with:
Note that with access to a machine account certificate, the attacker can then **authenticate to Kerberos** as the machine account. Using **S4U2Self**, an attacker can then obtain a **Kerberos service ticket to any service on the host** (e.g., CIFS, HTTP, RPCSS, etc.) as any user.
Ultimately, this gives an attack a machine persistence method.
## Account Persistence via Certificate Renewal - PERSIST3
Certificate templates have a **Validity Period** which determines how long an issued certificate can be used, as well as a **Renewal period** (usually 6 weeks). This is a window of **time before** the certificate **expires** where an **account can renew it** from the issuing certificate authority.
If an attacker compromises a certificate capable of domain authentication through theft or malicious enrolment, the attacker can **authenticate to AD for the duration of the certificate’s validity period**. The attacker, however, can r**enew the certificate before expiration**. This can function as an **extended persistence** approach that **prevents additional ticket** enrolments from being requested, which **can leave artifacts** on the CA server itself.
<details>
<summary><strong>Support HackTricks and get benefits!</strong></summary>
- Do you work in a **cybersecurity company**? Do you want to see your **company advertised in HackTricks**? or do you want to have access to the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
- **Join the** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** me on **Twitter** [**🐦**](https://github.com/carlospolop/hacktricks/tree/7af18b62b3bdc423e11444677a6a73d4043511e9/\[https:/emojipedia.org/bird/README.md)[**@carlospolopm**](https://twitter.com/carlospolopm)**.**
