Cisco Umbrella: Failed DNS Requests to Malware Domains: Same source and Multiple Destinations

Rule ID

PH_RULE_CiscoUmbrella_FailedDnsReqMalwareDomain_SameSrcAndMultDest

Default Status

Enabled

Description

Cisco Umbrella blocked a source from connecting to 2 or more distinct malware domains in a 15 minute interval.

Severity

MITRE ATT&CK® Tactics

Command And Control

MITRE ATT&CK® Techniques

T1071.004

Application Layer Protocol: DNS

Adversaries may communicate using the Domain Name System (DNS) application layer protocol to avoid detection/network filtering by blending in with existing traffic. Commands to the remote system, and often the results of those commands, will be embedded within the protocol traffic between the client and server.

https://attack.mitre.org/techniques/T1071/004

Impacts

Network

Data Source

Cisco Umbrella via AWS_S3, Cisco Umbrella via HTTPS_ADVANCED (Umbrella API)

Detection

Correlation

Remediation Guidance

Please confirm the intended domain should be blocked, and if so, investigate why endpoint is attempting to contact this domain.

Time Window

If the following pattern or patterns match an ingested event within the given time window in seconds, trigger an incident.

900 seconds

Trigger Conditions

If the following defined pattern/s occur within a 900 second time window.

umbrella

SubPattern Definitions

SubPattern Name: umbrella

This is the named definition of the event query, this is important if multiple subpatterns are defined to distinguish them.

SubPattern Query

This is the query logic that matches incoming events

eventType CONTAIN "CiscoUmbrella-DNS"  AND  fwAction = "blocked"  AND  webCategory CONTAIN "Malware"

Group by Attributes

This defines how matching events are aggregated, only events with the same matching attribute values are grouped into one unique incident ID

srcIpAddr

Aggregate Constraint

This is most typically a numerical constraint that defines when the rule should trigger an incident

COUNT(DISTINCT destDomain) >= 2

Incident Attribute Mapping

This section defines which fields in matching raw events should be mapped to the incident attributes in the resulting incident.

The available raw event attributes to map are limited to the group by attributes and the aggregate event constraint fields for each subpattern

 srcIpAddr=umbrella.srcIpAddr

FortiSIEM Rules