FortiSIEM Rules

Outbreak: BURNTCIGAR MS Signed Driver Malware detected on Network

Rule ID

PH_RULE_BURNTCIGAR_MS_Driver_Malware_Net

Default Status

Enabled

Description

BURNTCIGAR Microsoft Signed Driver Malware detected on network

Severity

9

Category

Security

MITRE ATT&CK® Tactics

Defense Evasion

Defense Evasion consists of techniques that adversaries use to avoid detection throughout their compromise. Techniques used for defense evasion include uninstalling/disabling security software or obfuscating/encrypting data and scripts. Adversaries also leverage and abuse trusted processes to hide and masquerade their malware. Other tactics’ techniques are cross-listed here when those techniques include the added benefit of subverting defenses.

https://attack.mitre.org/tactics/TA0005

MITRE ATT&CK® Techniques


T1036.001

Masquerading: Invalid Code Signature

Adversaries may attempt to mimic features of valid code signatures to increase the chance of deceiving a user, analyst, or tool. Code signing provides a level of authenticity on a binary from the developer and a guarantee that the binary has not been tampered with.

https://attack.mitre.org/techniques/T1036/001

Impacts

Network

Data Source

FortiGate via Syslog

Detection

Correlation

Remediation Guidance

Check if the source is patched for the CVE associated with the event. If yes then remove the host from the network and patch immediately. If host is not scanned then determine if the host is running the affected version of the application. If yes then patch immediately, else it is likely a false positive.

Time Window

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

300 seconds

Trigger Conditions

If the following defined pattern/s occur within a 300 second time window.

threat

SubPattern Definitions

SubPattern Name: threat

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 IN (Group@PH_SYS_EVENT_FortiGate_AV_Detected) AND ipsSignatureId IN (10116089,10115947) AND (srcIpAddr IN (Group@PH_SYS_NETWORK_ENTERPRISE_INTERNAL_NET) OR (destIpAddr IN (Group@PH_SYS_NETWORK_ENTERPRISE_INTERNAL_NET) AND fwAction NOT IN ("deny","dropped","block","blocked","ban-ip","alert_deny")))

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,destIpAddr

Aggregate Constraint

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

COUNT(*) >= 1

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=threat.srcIpAddr,
destIpAddr=threat.destIpAddr,
incidentCount=threat.COUNT(*)