Creating STIX Content¶
Creating STIX Domain Objects¶
To create a STIX object, provide keyword arguments to the type’s constructor:
In [3]:
from stix2 import Indicator
indicator = Indicator(name="File hash for malware variant",
labels=["malicious-activity"],
pattern="[file:hashes.md5 = 'd41d8cd98f00b204e9800998ecf8427e']")
print(indicator)
Out[3]:
{
"type": "indicator",
"id": "indicator--548af3be-39d7-4a3e-93c2-1a63cccf8951",
"created": "2018-04-05T18:32:24.193Z",
"modified": "2018-04-05T18:32:24.193Z",
"name": "File hash for malware variant",
"pattern": "[file:hashes.md5 = 'd41d8cd98f00b204e9800998ecf8427e']",
"valid_from": "2018-04-05T18:32:24.193659Z",
"labels": [
"malicious-activity"
]
}
Certain required attributes of all objects will be set automatically if not provided as keyword arguments:
- If not provided,
type
will be set automatically to the correct type. You can also provide the type explicitly, but this is not necessary:
In [4]:
indicator2 = Indicator(type='indicator',
labels=["malicious-activity"],
pattern="[file:hashes.md5 = 'd41d8cd98f00b204e9800998ecf8427e']")
Passing a value for type
that does not match the class being
constructed will cause an error:
In [5]:
indicator3 = Indicator(type='xxx',
labels=["malicious-activity"],
pattern="[file:hashes.md5 = 'd41d8cd98f00b204e9800998ecf8427e']")
InvalidValueError: Invalid value for Indicator 'type': must equal 'indicator'.
- If not provided,
id
will be generated randomly. If you provide anid
argument, it must begin with the correct prefix:
In [6]:
indicator4 = Indicator(id="campaign--63ce9068-b5ab-47fa-a2cf-a602ea01f21a",
labels=["malicious-activity"],
pattern="[file:hashes.md5 = 'd41d8cd98f00b204e9800998ecf8427e']")
InvalidValueError: Invalid value for Indicator 'id': must start with 'indicator--'.
For indicators, labels
and pattern
are required and cannot be
set automatically. Trying to create an indicator that is missing one of
these properties will result in an error:
In [7]:
indicator = Indicator()
MissingPropertiesError: No values for required properties for Indicator: (labels, pattern).
However, the required valid_from
attribute on Indicators will be set
to the current time if not provided as a keyword argument.
Once created, the object acts like a frozen dictionary. Properties can be accessed using the standard Python dictionary syntax:
In [8]:
indicator['name']
Out[8]:
'File hash for malware variant'
Or access properties using the standard Python attribute syntax:
In [9]:
indicator.name
Out[9]:
'File hash for malware variant'
Attempting to modify any attributes will raise an error:
In [10]:
indicator['name'] = "This is a revised name"
TypeError: 'Indicator' object does not support item assignment
In [11]:
indicator.name = "This is a revised name"
ImmutableError: Cannot modify 'name' property in 'Indicator' after creation.
To update the properties of an object, see the Versioning section.
Creating a Malware object follows the same pattern:
In [12]:
from stix2 import Malware
malware = Malware(name="Poison Ivy",
labels=['remote-access-trojan'])
print(malware)
Out[12]:
{
"type": "malware",
"id": "malware--3d7f0c1c-616a-4868-aa7b-150821d2a429",
"created": "2018-04-05T18:32:46.584Z",
"modified": "2018-04-05T18:32:46.584Z",
"name": "Poison Ivy",
"labels": [
"remote-access-trojan"
]
}
As with indicators, the type
, id
, created
, and modified
properties will be set automatically if not provided. For Malware
objects, the labels
and name
properties must be provided.
You can see the full list of SDO classes here.
Creating Relationships¶
STIX 2 Relationships are separate objects, not properties of the object
on either side of the relationship. They are constructed similarly to
other STIX objects. The type
, id
, created
, and modified
properties are added automatically if not provided. Callers must provide
the relationship_type
, source_ref
, and target_ref
properties.
In [13]:
from stix2 import Relationship
relationship = Relationship(relationship_type='indicates',
source_ref=indicator.id,
target_ref=malware.id)
print(relationship)
Out[13]:
{
"type": "relationship",
"id": "relationship--34ddc7b4-4965-4615-b286-1c8bbaa1e7db",
"created": "2018-04-05T18:32:49.474Z",
"modified": "2018-04-05T18:32:49.474Z",
"relationship_type": "indicates",
"source_ref": "indicator--548af3be-39d7-4a3e-93c2-1a63cccf8951",
"target_ref": "malware--3d7f0c1c-616a-4868-aa7b-150821d2a429"
}
The source_ref
and target_ref
properties can be either the ID’s
of other STIX objects, or the STIX objects themselves. For readability,
Relationship objects can also be constructed with the source_ref
,
relationship_type
, and target_ref
as positional (non-keyword)
arguments:
In [14]:
relationship2 = Relationship(indicator, 'indicates', malware)
print(relationship2)
Out[14]:
{
"type": "relationship",
"id": "relationship--0a646403-f7e7-4cfd-b945-cab5cde05857",
"created": "2018-04-05T18:32:51.417Z",
"modified": "2018-04-05T18:32:51.417Z",
"relationship_type": "indicates",
"source_ref": "indicator--548af3be-39d7-4a3e-93c2-1a63cccf8951",
"target_ref": "malware--3d7f0c1c-616a-4868-aa7b-150821d2a429"
}
Creating Bundles¶
STIX Bundles can be created by passing objects as arguments to the
Bundle constructor. All required properties (type
, id
, and
spec_version
) will be set automatically if not provided, or can be
provided as keyword arguments:
In [15]:
from stix2 import Bundle
bundle = Bundle(indicator, malware, relationship)
print(bundle)
Out[15]:
{
"type": "bundle",
"id": "bundle--f83477e5-f853-47e1-a267-43f3aa1bd5b0",
"spec_version": "2.0",
"objects": [
{
"type": "indicator",
"id": "indicator--548af3be-39d7-4a3e-93c2-1a63cccf8951",
"created": "2018-04-05T18:32:24.193Z",
"modified": "2018-04-05T18:32:24.193Z",
"name": "File hash for malware variant",
"pattern": "[file:hashes.md5 = 'd41d8cd98f00b204e9800998ecf8427e']",
"valid_from": "2018-04-05T18:32:24.193659Z",
"labels": [
"malicious-activity"
]
},
{
"type": "malware",
"id": "malware--3d7f0c1c-616a-4868-aa7b-150821d2a429",
"created": "2018-04-05T18:32:46.584Z",
"modified": "2018-04-05T18:32:46.584Z",
"name": "Poison Ivy",
"labels": [
"remote-access-trojan"
]
},
{
"type": "relationship",
"id": "relationship--34ddc7b4-4965-4615-b286-1c8bbaa1e7db",
"created": "2018-04-05T18:32:49.474Z",
"modified": "2018-04-05T18:32:49.474Z",
"relationship_type": "indicates",
"source_ref": "indicator--548af3be-39d7-4a3e-93c2-1a63cccf8951",
"target_ref": "malware--3d7f0c1c-616a-4868-aa7b-150821d2a429"
}
]
}