Detection rules › Sigma

Potential COLDSTEEL Persistence Service DLL Load

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

Detects a suspicious DLL load by an "svchost" process based on location and name that might be related to ColdSteel RAT. This DLL location and name has been seen used by ColdSteel as the service DLL for its persistence mechanism

MITRE ATT&CK coverage

TacticTechniques
PersistenceNo specific technique
StealthNo specific technique

Event coverage

ProviderEventTitle
SysmonEvent ID 7Image loaded

Rule body yaml

title: Potential COLDSTEEL Persistence Service DLL Load
id: 1d7a57da-02e0-4f7f-92b1-c7b486ccfed5
status: test
description: |
    Detects a suspicious DLL load by an "svchost" process based on location and name that might be related to ColdSteel RAT. This DLL location and name has been seen used by ColdSteel as the service DLL for its persistence mechanism
references:
    - https://www.ncsc.gov.uk/static-assets/documents/malware-analysis-reports/cold-steel/NCSC-MAR-Cold-Steel.pdf
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-05-02
tags:
    - attack.persistence
    - detection.emerging-threats
    - attack.stealth
logsource:
    product: windows
    category: image_load
detection:
    selection:
        Image|endswith: '\svchost.exe'
        ImageLoaded|endswith: '\AppData\Roaming\newdev.dll'
    condition: selection
falsepositives:
    - Unlikely
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith: '\svchost.exe'
    ImageLoaded|endswith: '\AppData\Roaming\newdev.dll'

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
Imageends_with
  • \svchost.exe corpus 23 (sigma 23)
ImageLoadedends_with
  • \AppData\Roaming\newdev.dll