Bug: Have network indicators in domain-ip MISP objects use kill_chain_phases "Network activity" instead of "network"

MISP-STIX usage

MISP core

Expected behavior

Have network related indicators in MISP objects (such as domain-ip and ip-port) use the "Network activity" phase_name in the kill_chain_phases

"kill_chain_phases": [
                    {
                        "kill_chain_name": "misp-category",
                        "phase_name": "Network activity"
                    }
                ]

Actual behavior

Currently they use "phase_name": "network" https://github.com/MISP/misp-stix/blob/f51194eb59c72d8955a9aa052a3d61c13e113f77/documentation/mapping/misp_objects_to_stix21.json#L779C18-L779C35

"kill_chain_phases": [
                    {
                        "kill_chain_name": "misp-category",
                        "phase_name": "network"
                    }
                ]

Steps to reproduce

Include a domain-ip object in a MISP export

Version

2.4.172

Python version

3.8

Relevant log output

No response

Extra attachments

No response

Code of Conduct

[X] I agree to follow this project's Code of Conduct

I checked in details the difference between domain|ip attributes and domain-ip objects to make sure the issue you describe here does not concern attributes, which category is Network activity.

Now given an example of a domain-ip object as the following:

{
    "uuid": "a6ef17d6-91cb-4a05-b10b-2f045daf874c",
    "Object": [
        {
            "name": "domain-ip",
            "meta-category": "network",
            "template_uuid": "43b3b146-77eb-4931-b4cc-b66c60f28734",
            "description": "A domain and IP address seen as a tuple",
            "template_version": "11",
            "uuid": "dc624447-684a-488f-9e16-f78f717d8efd",
            "Attribute": [
                {
                    "uuid": "63fa4060-98d3-4768-b18d-cfbc52f2d0ff",
                    "object_relation": "domain",
                    "value": "circl.lu",
                    "type": "domain",
                    "category": "Network activity",
                    "disable_correlation": false,
                    "to_ids": true
                },
                {
                    "uuid": "30e94901-9247-4d28-9746-ca4c0086201c",
                    "object_relation": "hostname",
                    "value": "circl.lu",
                    "type": "hostname",
                    "disable_correlation": false,
                    "to_ids": true,
                    "category": "Network activity"
                },
                {
                    "uuid": "fcbaf339-615a-409c-915f-034420dc90ca",
                    "object_relation": "ip",
                    "value": "149.13.33.14",
                    "type": "ip-dst",
                    "category": "Network activity",
                    "disable_correlation": false,
                    "to_ids": true
                },
                {
                    "uuid": "ff192fba-c594-4eb2-8432-cd335ad6647d",
                    "object_relation": "port",
                    "value": "8443",
                    "type": "port",
                    "category": "Network activity",
                    "disable_correlation": false,
                    "to_ids": false
                }
            ],
            "distribution": "5",
            "sharing_group_id": "0"
        }
    ],
    "info": "MISP-STIX-Converter test event",
    "published": false,
    "date": "2020-10-25",
    "Org": {
        "name": "MISP-Project",
        "uuid": "a0c22599-9e58-4da4-96ac-7051603fa951"
    },
    "Orgc": {
        "name": "MISP-Project",
        "uuid": "a0c22599-9e58-4da4-96ac-7051603fa951"
    }
}

The network phase name comes from the meta-category field as defined here and here

It is then intended to have the meta-category.
In this case, all the attributes are of type Network activity and it could make sense to have it as the category used to build the killchain phases.
But for automation purposes we always took the meta-category field as we can have different categories among different attributes (for instance, for files we could have Payload delivery, Artifacts dropped, External analysis, etc.)

I am still open for a discussion if you think we should change the way we generate the killchain phases. Let me know what you think of it

MISP / misp-stix