Dissecting Cobalt Strike using Python

dissect.cobaltstrike is a Python library for dissecting and parsing Cobalt Strike related data such as beacon payloads and Malleable C2 Profiles.

Installation

The library is available on PyPI. Use pip to install it:

$ pip install dissect.cobaltstrike

Or install using the full extra to automatically install dependencies for C2 and PCAP support:

$ pip install dissect.cobaltstrike[full]

dissect.cobaltstrike requires Python 3.7 or later.

Documentation

The project documentation can be found here: https://dissect-cobaltstrike.readthedocs.io

Basic Usage

Parse a Cobalt Strike beacon and extract some config settings

>>> from dissect.cobaltstrike.beacon import BeaconConfig

>>> bconfig = BeaconConfig.from_path("beacon.bin")

>>> hex(bconfig.watermark)
'0x5109bf6d'
>>> bconfig.protocol
'https'
>>> bconfig.version
<BeaconVersion 'Cobalt Strike 4.2 (Nov 06, 2020)', tuple=(4, 2), date=2020-11-06>

>>> bconfig.settings
mappingproxy({'SETTING_PROTOCOL': 8,
              'SETTING_PORT': 443,
              'SETTING_SLEEPTIME': 5000,
              'SETTING_MAXGET': 1048576,
              'SETTING_JITTER': 0, ...

>>> bconfig.settings["SETTING_C2_REQUEST"]
[('_HEADER', b'Connection: close'),
 ('_HEADER', b'Accept-Language: en-US'),
 ('BUILD', 'metadata'),
 ('MASK', True),
 ('BASE64', True),
 ('PREPEND', b'wordpress_ed1f617bbd6c004cc09e046f3c1b7148='),
 ('HEADER', b'Cookie')]

Parse a Malleable C2 Profile and read some configuration settings

>>> from dissect.cobaltstrike.c2profile import C2Profile
>>> profile = C2Profile.from_path("amazon.profile")
>>> profile.as_dict()
{'sleeptime': ['5000'],
 'jitter': ['0'],
 'maxdns': ['255'],
 'useragent': ['Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko'],
 'http-get.uri': ['/s/ref=nb_sb_noss_1/167-3294888-0262949/field-keywords=books'],
 'http-get.client.header': [('Accept', '*/*'), ('Host', 'www.amazon.com')],
 ...
}

>>> profile.properties["useragent"]
['Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko']

>>> profile.properties["http-get.uri"]
['/s/ref=nb_sb_noss_1/167-3294888-0262949/field-keywords=books']

Connect to Team Server as a Beacon Client

See also A Minimal Beacon Client tutorial in the documentation.

Parse and decrypt a PCAP containing Cobalt Strike traffic

See also the Decrypt Cobalt Strike PCAPs tutorial in the documentation.

$ beacon-pcap --extract-beacons 2021-06-15-Hancitor-with-Ficker-Stealer-and-Cobalt-Strike.pcap
[+] Found <BeaconConfig ['<redacted>']> at b'/ZsDK', extracted beacon payload to 'beacon-ZsDK.bin'
[+] Found <BeaconConfig ['<redacted>']> at b'/8mJm', extracted beacon payload to 'beacon-8mJm.bin'

$ beacon-pcap -p key.pem 2021-06-15-Hancitor-with-Ficker-Stealer-and-Cobalt-Strike.pcap --beacon beacon-8mJm.bin
<Beacon/BeaconMetadata packet_ts=2021-06-15 15:08:55.172675 src_ip=net.ipaddress('10.0.0.134') src_port=52886 dst_ip=net.ipaddress('<redacted>') dst_port=443 raw_http=b'GET /activity HTTP/1.1\r\nAccept: */*\r\nCookie: kR/OTFMhCYQpv09cXl2R7qEespVUfQ/8YahAbs1b+rEESbSzcAc44R9Klf4zH4GGYxT4dErzNQWimmMW5wQVQSEGFZ36mWc/beoUTQUGVUxcZWXl0t8WBO12qC6vsmRSV5uQO+qxz0Lbz1P/wOkWwbNM0XF9LhVjRrGYSR0Jlrc=\r\nUser-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; .NET CLR 2.0.50727)\r\nHost: <redacted>:443\r\nConnection: Keep-Alive\r\nCache-Control: no-cache\r\n\r\n' magic=48879 size=92 aes_rand=b'\xf9dA\xc8\x8b\x07\xe1:\xfa\np\xbc{`m\xe0' ansi_cp=58372 oem_cp=46337 bid=693615746 pid=6396 port=0 flag=4 ver_major=10 ver_minor=0 ver_build=19042 ptr_x64=0 ptr_gmh=1972243040 ptr_gpa=1972237648 ip=net.ipaddress('<redacted>') info=b'DESKTOP-X9JH6AW\ttabitha.gomez\tsvchost.exe'>
<Beacon/TaskPacket packet_ts=2021-06-15 15:09:56.371968 src_ip=net.ipaddress('<redacted>') src_port=443 dst_ip=net.ipaddress('10.0.0.134') dst_port=52894 raw_http=b'HTTP/1.1 200 OK\r\nDate: Tue, 15 Jun 2021 15:09:55 GMT\r\nContent-Type: application/octet-stream\r\nContent-Length: 48\r\n\r\nP\xc1\xf1\xa0{3 \xa8\x01}\xfe\xbcl\x8e\xa2\x81\xd7A2\xa3;\xe0\x91\xf5\x90\xdd]\xc5\x88`\xa2\x88\x93\x14-\xb4\xbb\x96\xf1\x1c\xd7\r\xa60\xfe\xc5\x9e\xd6' epoch=2021-06-15 15:09:55 total_size=16 command='COMMAND_SLEEP' size=8 data=b'\x00\x00\x00d\x00\x00\x00Z'>

License

dissect.cobaltstrike is developed and distributed under the MIT license.