Windows: Atera Agent Installation

Rule ID

PH_Rule_SIGMA_1229

Default Status

Enabled

Description

Detects successful installation of Atera Remote Monitoring & Management (RMM) agent as recently found to be used by Conti operators. This rule is adapted from https://github.com/SigmaHQ/sigma/blob/master/rules/windows/builtin/application/msiinstaller/win_software_atera_rmm_agent_install.yml

Severity

MITRE ATT&CK® Tactics

Command And Control

MITRE ATT&CK® Techniques

T1219

Remote Access Software

An adversary may use legitimate desktop support and remote access software, such as Team Viewer, Go2Assist, LogMein, AmmyyAdmin, etc, to establish an interactive command and control channel to target systems within networks. These services are commonly used as legitimate technical support software, and may be allowed by application control within a target environment.

https://attack.mitre.org/techniques/T1219

Impacts

Server

Data Source

Windows Security log via OMI or FortiSIEM Agent

Detection

Correlation

Remediation Guidance

No remediation guidance specified

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.

Filter

SubPattern Definitions

SubPattern Name: Filter

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="Win-App-MsiInstaller-1033" AND msg REGEXP ".*AteraAgent.*"

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

hostName,msg

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

hostName = Filter.hostName,
msg = Filter.msg

FortiSIEM Rules