Renamed ZOHO Dctask64 Execution — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: high. Source dates: 2020-01-28 / 2025-01-22.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 68ac85d0eb535b82980b0c82945e46f95e875a0191068f1a3fbc146e4d2aca56

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Renamed ZOHO Dctask64 Execution
id: 340a090b-c4e9-412e-bb36-b4b16fe96f9b
status: test
description: |
    Detects a renamed "dctask64.exe" execution, a signed binary by ZOHO Corporation part of ManageEngine Endpoint Central.
    This binary can be abused for DLL injection, arbitrary command and process execution.
references:
    - https://twitter.com/gN3mes1s/status/1222088214581825540
    - https://twitter.com/gN3mes1s/status/1222095963789111296
    - https://twitter.com/gN3mes1s/status/1222095371175911424
author: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)
date: 2020-01-28
modified: 2025-01-22
tags:
    - attack.privilege-escalation
    - attack.stealth
    - attack.t1036
    - attack.t1055.001
    - attack.t1202
    - attack.t1218
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Hashes|contains:
            - 'IMPHASH=6834B1B94E49701D77CCB3C0895E1AFD'
            - 'IMPHASH=1BB6F93B129F398C7C4A76BB97450BBA'
            - 'IMPHASH=FAA2AC19875FADE461C8D89DCF2710A3'
            - 'IMPHASH=F1039CED4B91572AB7847D26032E6BBF'
    filter_main_legit_name:
        Image|endswith: '\dctask64.exe'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://twitter.com/gN3mes1s/status/1222088214581825540
• https://twitter.com/gN3mes1s/status/1222095963789111296
• https://twitter.com/gN3mes1s/status/1222095371175911424