Reputation and DBotScore

DBot is the Cortex XSOAR machine learning bot which ingests information about indicators to determine if they are malicious or not. Since DBot requires a very specific dataset, we must format our data as per this article.

Context Format#

"DBotScore": {
  "Indicator" : "foo@demi.com",
  "Type": "email",
  "Vendor": "JoeSecurity",
  "Score": 3,
  "Reliability": "A - Completely reliable"
} 

The DBot score must be at the root level of the context and contain all the required keys as listed below.

Key	Meaning	Required
Indicator	The indicator value	Required
Type	Can be: ip, file, email, url, cve, account, cider, domainglob, certificate, or cryptocurrency	Required
Vendor	This is the vendor reporting the score of the indicator	Required
Score	An int representing the status of the indicator. See Score Types below	Required
Reliability	Reliability of the source providing the intelligence data. See Reliability Levels below	Optional

Reliability Level#

The reliability of an intelligence-data source influences the reputation of an indicator and the values for indicator fields when merging indicators.
The values are case sensitive.

  A+ - 3rd party enrichment  
  A - Completely reliable 
  B - Usually reliable  
  C - Fairly reliable  
  D - Not usually reliable  
  E - Unreliable  
  F - Reliability cannot be judged  

Score Types#

Dbot uses an integer to represent the reputation of an indicator.

Number	Reputation
0	Unknown
1	Good
2	Suspicious
3	Bad

Unknown#

Unknown score can be interpeted in two ways:

The vendor returns an "Unknown" score for the indicator.
The vendor returns nothing on the indicator.

In both cases we mark the indicator score as Unknown.

Malicious#

If the DBot score is returned as a "3" or "Bad", we need to add to the context that a malicious indicator was found. To do this, we add an additional key to the URL, IP, or File context called "Malicious" as shown below:

demisto.results({
     "Type": entryTypes["note"],
     "EntryContext": {
        "URL": {
            "Data": "STRING, The URL",
            "Malicious": {
                "Vendor": "STRING, Vendor reporting the malicious status",
                "Description": "STRING, Description of the malicious url"
            }
        },
         "File": {
            " SHA1/MD5/SHA256": "STRING, The File Hash",
            "Malicious": {
                "Vendor": "STRING, Vendor reporting the malicious status",
                "Description": "STRING, Description of the malicious hash"
            }
        },
         "IP": {
            "Address": "STRING, The IP",
            "Malicious":{
                "Vendor": "STRING, Vendor reporting malicious",
                "Description": "STRING, Description about why IP was determined malicious"
        },
        },
         "Domain": {
            "Name": "STRING, The Domain",
            "Malicious": {
                "Vendor": "STRING, Vendor reporting the malicious status",
                "Description": "STRING, Description of the malicious domain"
            }
        }
    }
})

Malicious has two key values, "Vendor" and "Description". Vendor is the entity reporting the malicious indicator and description explains briefly what was found. For example:

"URL": {
    "Data": "http://viruswarehouse.com",
    "Malicious": {
        "Vendor": "VirusTotal",
        "Description": "Wannacry ransomware detected"
    }
}

Please Note: We are unable to use the Cortex XSOAR Transformers (DT) within the DBot score context.

For example, using the following in your DBot context, will not work:

DBotScore(val.Indicator == obj.Indicator)