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, dnspython and future. ldapdomaindump runs on both python 2 and 3.

Dependencies can be installed manually with pip install ldap3 dnspython future, but should in most cases be handled by pip when you install the main package either from git or pypi.

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 (try 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. Note that these files are only compatible with BloodHound 1.x which is quite old. There are no plans to support the latest version as the BloodHound.py project was made for this. With the DCOnly collection method this tool will also only talk to LDAP and collect more information than ldapdomaindump would.

Visualizing dump with a pretty output like enum4linux

LDAPDomainDump includes a utility that can be used to output ldapdomaindumps .json files to an enum4linux like output. The utility is called ldd2pretty and is added to your path upon installation. Alternatively you can run it with python -m ldapdomaindump.pretty or with python ldapdomaindump/pretty.py if you are running it from the source.

License

MIT