huntrule

DNS Queries to Low-Reputation Effective TLDs (eTLD) via Known Bad TLD List

Alerts on DNS queries targeting domains under known low-reputation eTLD suffixes from an external threat-intel list.

FreeReviewedSigma · Medium · v5
Category
dns
Author
Norbert Jaśniewicz (AlphaSOC) (SigmaHQ), DRL 1.1
Published
2025-08-04
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

C2

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule flags DNS queries whose domain names end with specific low-reputation effective top-level domains (eTLDs). Attackers may use these domains to blend in with less-trusted infrastructure during command-and-control or initial access. The detection relies on DNS query telemetry containing the queried domain name and matches it against a predefined list of high-risk suffixes sourced from AlphaSOC threat intelligence, updated monthly.

Reporting behind it

Related detections9 linkedT1071.004 — drag to rearrange
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Suspicious DNS Query to Dynamic DNS and Tunneling Providers Abused by RATs
Suspicious UPSTYLE Command Channel Pattern in Web Requests via CVE-2024-3400
Suspicious DNS C2 to Microsoft Typosquat Domain
Suspicious DNS Queries to Simitor Tracking Tunnel Infrastructure
Suspicious DNS Queries to Secshow Open Resolver Scanning Infrastructure
Suspicious OpenMetadata Exploit Interactsh OAST Callback (via process_creation)
Suspicious Outlook Process Spawning Network Utilities for NotDoor C2 (via process_creation)
Malicious DNS Query To fdmpkg C2 Domain via DNS Query
DNS Queries to Low-Reputation Effective TLDs (eTLD) via Known Bad TLD List
Pivot detection · T1071.004 · 9 related

Changelog

v5
  1. v5
    Candidate ingested via manual entry.2026-07-31
  2. v4
    Candidate ingested via manual entry.2026-07-31
  3. v3
    Candidate ingested via manual entry.2026-07-31
  4. v2
    Candidate ingested via manual entry.2026-07-31
  5. 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.