Active Directory information dumper via LDAP

Introduction
In an Active Directory domain, a lot of interesting information can be retrieved via LDAP by any authenticated user (or machine). This makes LDAP an interesting protocol for gathering information in the recon phase of a pentest of an internal network. A problem is that data from LDAP often is not available in an easy to read format.
ldapdomaindump is a tool which aims to solve this problem, by collecting and parsing information available via LDAP and outputting it in a human readable HTML format, as well as machine readable json and csv/tsv/greppable files.
The tool was designed with the following goals in mind:

• Easy overview of all users/groups/computers/policies in the domain
• Authentication both via username and password, as with NTLM hashes (requires ldap3 >=1.3.1)
• Possibility to run the tool with an existing authenticated connection to an LDAP service, allowing for integration with relaying tools such as impackets ntlmrelayx

The tool outputs several files containing an overview of objects in the domain:

• domain_groups: List of groups in the domain
• domain_users: List of users in the domain
• domain_computers: List of computer accounts in the domain
• domain_policy: Domain policy such as password requirements and lockout policy
• domain_trusts: Incoming and outgoing domain trusts, and their properties

As well as two grouped files:

• domain_users_by_group: Domain users per group they are member of
• domain_computers_by_os: Domain computers sorted by Operating System

Dependencies and installation
Requires ldap3 > 2.0 and dnspython
Both can be installed with pip install ldap3 dnspython
The ldapdomaindump package can be installed with python setup.py install from the git source, or for the latest release with pip install ldapdomaindump.

Usage
There are 3 ways to use the tool:

• With just the source, run python ldapdomaindump.py
• After installing, by running python -m ldapdomaindump
• After installing, by running ldapdomaindump

Help can be obtained with the -h switch:

usage: ldapdomaindump.py [-h] [-u USERNAME] [-p PASSWORD] [-at {NTLM,SIMPLE}]
                          [-o DIRECTORY] [--no-html] [--no-json] [--no-grep]
                          [--grouped-json] [-d DELIMITER] [-r] [-n DNS_SERVER]
                          [-m]
                          HOSTNAME
 
 Domain information dumper via LDAP. Dumps users/computers/groups and
 OS/membership information to HTML/JSON/greppable output.
 
 Required options:
   HOSTNAME              Hostname/ip or ldap://host:port connection string to
                         connect to (use ldaps:// to use SSL)
 
 Main options:
   -h, --help            show this help message and exit
   -u USERNAME, --user USERNAME
                         DOMAIN\username for authentication, leave empty for
                         anonymous authentication
   -p PASSWORD, --password PASSWORD
                         Password or LM:NTLM hash, will prompt if not    specified
   -at {NTLM,SIMPLE}, --authtype {NTLM,SIMPLE}
                         Authentication type (NTLM or SIMPLE, default: NTLM)
 
 Output options:
   -o DIRECTORY, --outdir DIRECTORY
                         Directory in which the dump will be saved (default:
                         current)
   --no-html             Disable HTML output
   --no-json             Disable JSON output
   --no-grep             Disable Greppable output
   --grouped-json        Also write json files for grouped files (default:
                         disabled)
   -d DELIMITER, --delimiter DELIMITER
                         Field delimiter for greppable output (default: tab)
 
 Misc options:
   -r, --resolve         Resolve computer hostnames (might take a while and
                         cause high traffic on large networks)
   -n DNS_SERVER, --dns-server DNS_SERVER
                         Use custom DNS resolver instead of system DNS (t   ry a
                         domain controller IP)
   -m, --minimal         Only query minimal set of attributes to limit memmory
                         usage

Options

Authentication
Most AD servers support NTLM authentication. In the rare case that it does not, use --authtype SIMPLE.

Output formats
By default the tool outputs all files in HTML, JSON and tab delimited output (greppable). There are also two grouped files (users_by_group and computers_by_os) for convenience. These do not have a greppable output. JSON output for grouped files is disabled by default since it creates very large files without any data that isn't present in the other files already.

DNS resolving
An important option is the -r option, which decides if a computers DNSHostName attribute should be resolved to an IPv4 address. While this can be very useful, the DNSHostName attribute is not automatically updated. When the AD Domain uses subdomains for computer hostnames, the DNSHostName will often be incorrect and will not resolve. Also keep in mind that resolving every hostname in the domain might cause a high load on the domain controller.

Minimizing network and memory usage
By default ldapdomaindump will try to dump every single attribute it can read to disk in the .json files. In large networks, this uses a lot of memory (since group relationships are currently calculated in memory before being written to disk). To dump only the minimal required attributes (the ones shown by default in the .html and .grep files), use the --minimal switch.

Visualizing groups with BloodHound
LDAPDomainDump includes a utility that can be used to convert ldapdomaindumps .json files to CSV files suitable for BloodHound. The utility is called ldd2bloodhound and is added to your path upon installation. Alternatively you can run it with python -m ldapdomaindump.convert or with python ldapdomaindump/convert.py if you are running it from the source. The conversion tool will take the users/groups/computers/trusts .json file and convert those to group_membership.csv and trust.csv which you can add to BloodHound.