Windows Security: Suspicious SAMTHEADMIN-* Computer/Account Names Ending with $

Alerts on Windows Security events with computer account names starting SAMTHEADMIN- and ending with $.

FreeReviewedSigma · Critical · v2

Product: windows
Service: security
Author: elhoim (SigmaHQ), DRL 1.1
Published: 2022-09-09
Updated: 2026-07-31

ATT&CK techniques

Initial Access → Defense Evasion

Recon
Resource Dev
Initial Access
- T1078Valid Accounts
Execution
Persistence
- T1078Valid Accounts
Priv Esc
- T1078Valid Accounts
Defense Evasion
- T1078Valid Accounts
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule flags Windows Security events where a computer or related account name starts with "SAMTHEADMIN-" and ends with "$". Such naming patterns can indicate automated or hacktool-generated account creation, which attackers may use for initial access, persistence, privilege escalation, or stealth. It relies on telemetry fields that include SamAccountName and TargetUserName from Windows Security logging.

Reporting behind it

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Windows Security: Suspicious SAMTHEADMIN-* Computer/Account Names Ending with $

Pivot detection · T1078 · 9 related

Changelog

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.

windows-security-suspicious-samtheadmin-computer-account-names-39698b3f

title: "Windows Security: Suspicious SAMTHEADMIN-* Computer/Account Names Ending with $"
id: 25059ffa-b522-462c-981b-a8f15ced8a98
status: test
description: This rule flags Windows Security events where a computer or related account name starts with "SAMTHEADMIN-" and ends with "$". Such naming patterns can indicate automated or hacktool-generated account creation, which attackers may use for initial access, persistence, privilege escalation, or stealth. It relies on telemetry fields that include SamAccountName and TargetUserName from Windows Security logging.
references:
  - https://twitter.com/malmoeb/status/1511760068743766026
  - https://github.com/helloexp/0day/blob/614227a7b9beb0e91e7e2c6a5e532e6f7a8e883c/00-CVE_EXP/CVE-2021-42287/sam-the-admin/sam_the_admin.py
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/builtin/security/win_security_susp_computer_name.yml
author: elhoim, Huntrule Team
date: 2022-09-09
modified: 2023-01-04
tags:
  - attack.initial-access
  - cve.2021-42278
  - cve.2021-42287
  - attack.persistence
  - attack.privilege-escalation
  - attack.stealth
  - attack.t1078
logsource:
  service: security
  product: windows
detection:
  selection1:
    SamAccountName|startswith: SAMTHEADMIN-
    SamAccountName|endswith: $
  selection2:
    TargetUserName|startswith: SAMTHEADMIN-
    TargetUserName|endswith: $
  condition: 1 of selection*
falsepositives:
  - Unknown
level: critical
license: DRL-1.1
related:
  - id: 39698b3f-da92-4bc6-bfb5-645a98386e45
    type: derived

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