detection.wiki

Detection rules › Sigma

WannaCry Ransomware Activity

Status
test
Severity
critical
Log source
product windows, category process_creation
Author
Florian Roth (Nextron Systems), Tom U. @c_APT_ure (collection), oscd.community, Jonhnathan Ribeiro
Source
github.com/SigmaHQ/sigma

Detects WannaCry ransomware activity

MITRE ATT&CK coverage

TacticTechniques
Defense ImpairmentT1222.001 File and Directory Permissions Modification: Windows Permissions
DiscoveryT1083 File and Directory Discovery
Lateral MovementT1210 Exploitation of Remote Services
ImpactT1486 Data Encrypted for Impact, T1490 Inhibit System Recovery

Event coverage

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

Rule body yaml

title: WannaCry Ransomware Activity
id: 41d40bff-377a-43e2-8e1b-2e543069e079
status: test
description: Detects WannaCry ransomware activity
references:
    - https://www.hybrid-analysis.com/sample/ed01ebfbc9eb5bbea545af4d01bf5f1071661840480439c6e5babe8e080e41aa?environmentId=100
    - https://x.com/nas_bench/status/1868639048484425963
author: Florian Roth (Nextron Systems), Tom U. @c_APT_ure (collection), oscd.community, Jonhnathan Ribeiro
date: 2019-01-16
modified: 2025-10-18
tags:
    - attack.lateral-movement
    - attack.defense-impairment
    - attack.t1210
    - attack.discovery
    - attack.t1083
    - attack.t1222.001
    - attack.impact
    - attack.t1486
    - attack.t1490
    - detection.emerging-threats
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith:
              - '\tasksche.exe'
              - '\mssecsvc.exe'
              - '\taskdl.exe'
              - '\taskhsvc.exe'
              - '\taskse.exe'
              - '\111.exe'
              - '\lhdfrgui.exe'
              # - '\diskpart.exe'  # cannot be used in a rule of level critical
              - '\linuxnew.exe'
              - '\wannacry.exe'
        - Image|contains: 'WanaDecryptor'
    selection_cmd:
        CommandLine|contains: '@Please_Read_Me@.txt'
    condition: 1 of selection_*
falsepositives:
    - Unknown
level: critical

Stages and Predicates

Stage 0: condition

1 of selection_*

Stage 1: selection_img

selection_img:
    - Image|endswith:
          - '\tasksche.exe'
          - '\mssecsvc.exe'
          - '\taskdl.exe'
          - '\taskhsvc.exe'
          - '\taskse.exe'
          - '\111.exe'
          - '\lhdfrgui.exe'
          - '\linuxnew.exe'
          - '\wannacry.exe'
    - Image|contains: 'WanaDecryptor'

Stage 2: selection_cmd

selection_cmd:
    CommandLine|contains: '@Please_Read_Me@.txt'

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
  • @Please_Read_Me@.txt
Imageends_with
  • \111.exe
  • \lhdfrgui.exe
  • \linuxnew.exe
  • \mssecsvc.exe
  • \taskdl.exe
  • \taskhsvc.exe
  • \tasksche.exe
  • \taskse.exe
  • \wannacry.exe
Imagematch
  • WanaDecryptor