Detect Wannacry killswitch DNS queries to hardcoded domains

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.001Web Protocols
Exfiltration
Impact

What it detects

This rule flags DNS queries for specific hardcoded domain names associated with the Wannacry killswitch. Attackers may use such domains to control ransomware behavior based on external DNS resolution. Detection relies on DNS query telemetry that includes the queried domain name.

Reporting behind it

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Detect Wannacry killswitch DNS queries to hardcoded domains

Pivot detection · T1071.001 · 9 related

Changelog

v2

v2
Candidate ingested via manual entry.2026-07-31
v1
No changelog recorded for this version.2026-07-30

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

detect-wannacry-killswitch-domains-in-dns-queries-3eaf6218

title: Detect Wannacry killswitch DNS queries to hardcoded domains
id: 39cb9c1a-7c25-48c3-bb84-36ce6d77b2b4
status: test
description: This rule flags DNS queries for specific hardcoded domain names associated with the Wannacry killswitch. Attackers may use such domains to control ransomware behavior based on external DNS resolution. Detection relies on DNS query telemetry that includes the queried domain name.
references:
  - https://www.mandiant.com/resources/blog/wannacry-ransomware-campaign
  - https://github.com/SigmaHQ/sigma/blob/master/rules/network/dns/net_dns_wannacry_killswitch_domain.yml
author: Mike Wade, Huntrule Team
date: 2020-09-16
modified: 2022-03-24
tags:
  - attack.command-and-control
  - attack.t1071.001
logsource:
  category: dns
detection:
  selection:
    query:
      - ifferfsodp9ifjaposdfjhgosurijfaewrwergwea.testing
      - ifferfsodp9ifjaposdfjhgosurijfaewrwergwea.test
      - ifferfsodp9ifjaposdfjhgosurijfaewrwergwea.com
      - ayylmaotjhsstasdfasdfasdfasdfasdfasdfasdf.com
      - iuqssfsodp9ifjaposdfjhgosurijfaewrwergwea.com
  condition: selection
falsepositives:
  - Analyst testing
level: high
license: DRL-1.1
related:
  - id: 3eaf6218-3bed-4d8a-8707-274096f12a18
    type: derived

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