detection.wiki

Detection rules › Sigma

Root Certificate Installed From Susp Locations

Status
test
Severity
high
Log source
product windows, category process_creation
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Adversaries may install a root certificate on a compromised system to avoid warnings when connecting to adversary controlled web servers.

MITRE ATT&CK coverage

TacticTechniques
Defense ImpairmentT1553.004 Subvert Trust Controls: Install Root Certificate

Event coverage

ProviderEventTitle
SysmonEvent ID 1Process creation
Security-AuditingEvent ID 4688A new process has been created.

Rule body yaml

title: Root Certificate Installed From Susp Locations
id: 5f6a601c-2ecb-498b-9c33-660362323afa
status: test
description: Adversaries may install a root certificate on a compromised system to avoid warnings when connecting to adversary controlled web servers.
references:
    - https://www.microsoft.com/security/blog/2022/09/07/profiling-dev-0270-phosphorus-ransomware-operations/
    - https://learn.microsoft.com/en-us/powershell/module/pki/import-certificate?view=windowsserver2022-ps
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-09-09
modified: 2023-01-16
tags:
    - attack.defense-impairment
    - attack.t1553.004
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        CommandLine|contains|all:
            - 'Import-Certificate'
            - ' -FilePath '
            - 'Cert:\LocalMachine\Root'
        CommandLine|contains:
            - '\AppData\Local\Temp\'
            - ':\Windows\TEMP\'
            - '\Desktop\'
            - '\Downloads\'
            - '\Perflogs\'
            - ':\Users\Public\'
    condition: selection
falsepositives:
    - Unlikely
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    CommandLine|contains|all:
        - 'Import-Certificate'
        - ' -FilePath '
        - 'Cert:\LocalMachine\Root'
    CommandLine|contains:
        - '\AppData\Local\Temp\'
        - ':\Windows\TEMP\'
        - '\Desktop\'
        - '\Downloads\'
        - '\Perflogs\'
        - ':\Users\Public\'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
CommandLinematch
  • -FilePath
  • :\Users\Public\ corpus 18 (sigma 18)
  • :\Windows\TEMP\ corpus 16 (sigma 16)
  • Cert:\LocalMachine\Root
  • Import-Certificate
  • \AppData\Local\Temp\ corpus 26 (sigma 26)
  • \Desktop\ corpus 13 (sigma 13)
  • \Downloads\ corpus 14 (sigma 14)
  • \Perflogs\ corpus 3 (sigma 3)