mwdb-iocextract

Python 3 library useful for getting structured IOC data from mwdb configs.

Why?

Warning: this project is only relevant to mwdb users. Mwdb is our solution for storing and extracting malware. If you're a white-hat security researcher interested in getting access to it, send a request via our website or email info@cert.pl.

Mwdb configs are pretty unstructured (they're basically JSONs with some additional metadata). On the other hand, automated processing often requires structured data.

For example, extracting and processing URLs is a common use case for analysts. Sadly, every module stores them a bit differently (and due to backward compatibility we're not ready to change that).

For example, compare how ISFB module reports its URls:

"domains": [
    {
        "cnc": "http://fantaniz.ru"
    },
    {
        "cnc": "http://snezhkaie.ru"
    }
]

Lokibot:

"urls": [
    {
        "url": "http://hockvvee.com/chief4/five/fre.php"
    },
    {
        "url": "kbfvzoboss.bid/alien/fre.php"
    },
    {
        "url": "alphastand.top/alien/fre.php"
    }
]

And mirai:

"cncs": [
    {
        "host": "107.160.244.5",
        "port": 1024
    }
]

With mwdb-iocextract you can handle all these (and dozens more) config types in the same way:

from mwdb_iocextract import parse

config_family = "mirai"
config_data = {
    "cncs": [
        {
            "host": "107.160.244.5",
            "port": 1024
        }
    ],
    "table_key": "0xdedefbaf",
    "variant": "OWARI",
    "type": "mirai"
}

iocs = parse(config_family, config_data)
print(iocs.prettyprint())

> python test.py
NetLoc 107.160.244.5:1024

See below for more usage examples.

Info

Contact email: msm@cert.pl or info@cert.pl

Install

$ pip install mwdb-iocextract

You can always find the newest version here:

https://pypi-hypernode.com/project/mwdb-iocextract/

Usage

Scan mwdb

In a typical use case, you'll probably want to get and parse configs downloaded directly from mwdb. To access the mwdb api and download recent configs we utilise the mwdblib (our official API bindings for mwdb]).

from mwdb_iocextract import parse
from mwdblib import Malwarecage


def main():
    # See also https://mwdblib.readthedocs.io/en/latest/index.html
    mwdb = Malwarecage()
    mwdb.login("msm", "my_secret_password")

    for cfg in mwdb.recent_configs():
        if cfg.type != "static":
            # Not all configs are created equal.
            # This code only deals with "static" configs, i.e. configs
            # extracted from malware/memory dumps
            continue
        try:
            iocs = parse(cfg.family, cfg.cfg)
        except FamilyNotSupportedYetError:
            # This means, that your mwdb_iocextract version does not
            # support this family. Consider updating it (it may take
            # us a few days to add support for a new family)
            continue
        print(iocs.prettyprint())  # convert all IoCs to string


if __name__ == "__main__":
    main()

Working with IOCs

The result of a parse() is a IocCollection object. You can use it like a normal Python object, for example:

iocs = parse(cfg.family, cfg.cfg)

for rsa_key in iocs.rsa_keys:
    e = rsa_key.e  # get e
    n = rsa_key.n  # get n

for netloc in iocs.network_locations:
    ip = netloc.ip  # get IP if known
    domain = netloc.domain  # get domain if known
    host = netloc.host  # get domain if known, otherwise IP
    port = netloc.port  # get port if known
    loctype = netloc.location_type  # get type (usually CNC)
    url = netloc.url  # get host + port + path

for key_type, key_data in iocs.keys:
    # key_type - for example "rc4"
    # key_data - hexencoded bytes, for example "6123541243"
    pass

iocs.passwords  # passwords or similar data found in the config
iocs.mutexes  # mutex names used by malware
iocs.dropped_filenames  # filenames dropped on the disk
iocs.emails  # emails used by malware

MISP integration

You can convert IocCollection to a MISP object:

def upload_to_misp(family, config):
    try:
        iocs = parse(family, config)
    except FamilyNotSupportedYetError:
        return

    if not iocs:
        # Nothing actionable found - skip the config
        return

    # Be careful not to upload duplicated events.
    # We use uuid5s generated from mwdb dhash as unique deterministic UUIDs.
    event = MISPEvent()
    event.add_tag(f"mwdb:family:{family}")
    event.info = f"Malware configuration ({family})"

    for o in iocs.to_misp():
        event.add_object(o)

    misp = ExpandedPyMISP(MISP_URL, MISP_KEY, MISP_VERIFYCERT)
    misp.add_event(event)

Alternatively, depending on who you represent, you can reach out to us and we can discuss sharing our MISP with you.