Which SIEM platforms have a T1690 detection rule?

df00tech provides T1690 (Impair Command History Logging) detection queries for 7 SIEM platforms: Microsoft Sentinel / Defender, Splunk, Elastic Security (EQL), IBM QRadar (AQL), Sumo Logic CSE, Google Chronicle / SecOps, CrowdStrike LogScale (CQL).

What data sources are required to detect Impair Command History Logging (T1690)?

Detecting Impair Command History Logging requires the following data sources: Process: Process Creation, Command: Command Execution, Sensor Health: Host Status.

What severity and confidence is the T1690 detection?

The T1690 detection is rated medium severity with medium confidence.

What are common false positives for T1690?

Common false positives for T1690 include: Developers or sysadmins who habitually set HISTCONTROL=ignorespace for convenience when typing sensitive commands (e.g., inline passwords); Automated provisioning or hardening scripts that configure shell history settings as part of baseline configuration; Docker container entrypoint scripts that disable history logging in ephemeral environments.

T1690 IBM QRadar · QRadar

Detect Impair Command History Logging in IBM QRadar

Adversaries may impair command history logging to hide commands they run on a compromised system. On Linux and macOS, this involves manipulating HISTFILE, HISTFILESIZE, HISTSIZE, and HISTCONTROL environment variables, or redirecting history to /dev/null. On Windows, adversaries may modify PSReadLine settings to disable PowerShell command history. On network devices, adversaries may disable command logging entirely.

MITRE ATT&CK

Tactic: Defense Impairment
Technique: T1690 Prevent Command History Logging
Canonical reference: https://attack.mitre.org/techniques/T1690/

QRadar Detection Query

IBM QRadar (QRadar)

sql

SELECT
  DATEFORMAT(starttime, 'YYYY-MM-dd HH:mm:ss') AS event_time,
  sourceip,
  username,
  LOGSOURCENAME(logsourceid) AS log_source,
  CATEGORYNAME(category) AS category_name,
  "CommandLine",
  CASE
    WHEN "CommandLine" ILIKE '%unset HISTFILE%' OR "CommandLine" ILIKE '%HISTFILE=/dev/null%' THEN 'HISTFILE Disabled'
    WHEN "CommandLine" ILIKE '%HISTFILESIZE=0%' OR "CommandLine" ILIKE '%HISTSIZE=0%' THEN 'History Size Zeroed'
    WHEN "CommandLine" ILIKE '%HISTCONTROL%' THEN 'HISTCONTROL Modified'
    WHEN "CommandLine" ILIKE '%history -c%' THEN 'History Cleared'
    WHEN "CommandLine" ILIKE '%set +o history%' THEN 'History Disabled'
    WHEN "CommandLine" ILIKE '%SaveNothing%' OR "CommandLine" ILIKE '%HistorySavePath%' THEN 'PSReadLine Tampered'
    WHEN "CommandLine" ILIKE '%ConsoleHost_history%' THEN 'PS History File Deleted'
    WHEN "CommandLine" ILIKE '%bash_history%' AND ("CommandLine" ILIKE '%rm %' OR "CommandLine" ILIKE '%truncate%' OR "CommandLine" ILIKE '%ln -sf%') THEN 'History File Deleted'
    ELSE 'Other'
  END AS tamper_method,
  CASE
    WHEN LOGSOURCETYPEID(logsourceid) = 12 THEN 'Windows'
    WHEN LOGSOURCETYPEID(logsourceid) IN (71, 233, 352) THEN 'Linux/macOS'
    ELSE 'Unknown'
  END AS platform
FROM events
WHERE
  starttime > NOW() - 1 DAYS
  AND (
    "CommandLine" ILIKE '%unset HISTFILE%'
    OR "CommandLine" ILIKE '%HISTFILE=/dev/null%'
    OR "CommandLine" ILIKE '%HISTFILESIZE=0%'
    OR "CommandLine" ILIKE '%HISTSIZE=0%'
    OR "CommandLine" ILIKE '%HISTCONTROL=ignoreboth%'
    OR "CommandLine" ILIKE '%HISTCONTROL=ignorespace%'
    OR "CommandLine" ILIKE '%set +o history%'
    OR "CommandLine" ILIKE '%history -c%'
    OR "CommandLine" ILIKE '%history -w /dev/null%'
    OR "CommandLine" ILIKE '%Set-PSReadlineOption%SaveNothing%'
    OR "CommandLine" ILIKE '%Set-PSReadLineOption%HistorySavePath%'
    OR "CommandLine" ILIKE '%Remove-Item%ConsoleHost_history%'
    OR "CommandLine" ILIKE '%del%ConsoleHost_history%'
    OR ("CommandLine" ILIKE '%bash_history%'
        AND ("CommandLine" ILIKE '%rm -%' OR "CommandLine" ILIKE '%truncate -s 0%' OR "CommandLine" ILIKE '%ln -sf /dev/null%'))
  )
ORDER BY starttime DESC

medium severity medium confidence

Detects command history tampering across Linux/macOS and Windows endpoints ingested into QRadar. Queries process execution logs for shell environment variable manipulation, history file deletion, and PSReadLine configuration changes that prevent command logging. Uses CommandLine field populated by Sysmon, auditd, or EDR integrations.

Data Sources

Sysmon for Windows (via WinCollect or DSM)Linux auditd via QRadar DSMCrowdStrike Falcon via QRadar appCarbon Black via QRadar DSM

Required Tables

events

False Positives & Tuning

Automated infrastructure-as-code tools (Ansible, Chef, Puppet) that set HISTCONTROL=ignorespace to avoid recording plaintext credentials passed as command arguments during provisioning
Docker container initialization scripts that clear or redirect bash history as part of image build or ephemeral container startup to reduce attack surface
Security teams running STIG compliance enforcement scripts that modify history settings as part of baseline hardening on managed Linux hosts

Other platforms for T1690

Microsoft Sentinel (KQL) Splunk (SPL) Elastic Security (Elastic) Sumo Logic CSE (Sumo) Google Chronicle (YARA-L) CrowdStrike LogScale (LogScale) All platforms (combined) →

Testing Methodology

Validate this detection against 3 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.

Test 1 Disable Bash History via HISTFILE

Expected signal: Auditd execve record for the shell session showing 'unset HISTFILE'. Process creation event in MDE. No bash_history entries will be written for subsequent commands.
Test 2 Redirect History to /dev/null (BPFDoor Pattern)

Expected signal: Auditd execve record. The process /proc/<PID>/environ will show HISTFILE=/dev/null.
Test 3 Disable PSReadLine History on Windows

Expected signal: Sysmon Event ID 1: powershell.exe with CommandLine containing 'Set-PSReadlineOption'. PowerShell ScriptBlock Log Event ID 4104.

Last updated: 2026-04-21 Research depth: deep

References (5)

Response Playbook

Triage

Determine the platform (Linux/macOS vs Windows) and the specific history impairment method used
Check the user account — is this a known admin or developer who might have legitimate reasons to modify history settings?
Look for the full session context — what other commands were executed before and after the history tampering?
On Linux: check if HISTFILE was redirected to /dev/null (BPFDoor indicator) or if MYSQL_HISTFILE was also set to /dev/null
Check for other defense evasion indicators on the same host — timestamp stomping, log deletion, audit system tampering

Containment

Restore history file from backup if available (HISTFILE may still exist on disk if only the environment variable was unset)
Enable alternative command logging that cannot be easily bypassed (auditd syscall logging on Linux, ScriptBlock Logging on Windows)
If the host is suspected compromised: isolate and begin forensic analysis
Reset user credentials if the account appears compromised
Deploy enhanced monitoring (auditd rules for execve syscalls) to capture commands regardless of shell history settings

Evidence Collection

Linux: /var/log/auth.log or /var/log/secure for session start/end times
Linux: auditd logs with execve syscall rules capture all executed commands regardless of HISTFILE settings
Linux: /proc/<PID>/environ for running processes to check HISTFILE/MYSQL_HISTFILE values
Linux: ~/.bash_history, ~/.zsh_history — check file timestamps, size, and content
Windows: $env:APPDATA\Microsoft\Windows\PowerShell\PSReadLine\ConsoleHost_history.txt
Windows: PowerShell ScriptBlock Logging (Event ID 4104) captures commands even if PSReadLine is disabled

Escalation Criteria

!HISTFILE set to /dev/null combined with MYSQL_HISTFILE=/dev/null — strong indicator of BPFDoor or similar backdoor
!History impairment on a production server or bastion host that should have strict audit logging
!Multiple users on the same host showing history impairment (indicates automated script or widespread compromise)
!History tampering followed by evidence of lateral movement, data exfiltration, or persistence installation

Investigation Guide

Forensic Artifacts

>File System: ~/.bash_history, ~/.zsh_history, ~/.sh_history — check timestamps, size, last modified
>File System: /proc/<PID>/environ — environment variables of running processes may reveal HISTFILE=/dev/null
>File System: $env:APPDATA\Microsoft\Windows\PowerShell\PSReadLine\ConsoleHost_history.txt — PowerShell history
>Auditd: execve syscall records capture commands even when HISTFILE is disabled
>Auditd: syscall records for unlink/rename on history files
>Windows: Registry HKCU\Console\PSReadLine — PSReadLine configuration

Tuning Guidance

HISTCONTROL=ignorespace is commonly set by default in some Linux distributions and by users who occasionally type sensitive commands (passwords, tokens). Consider only alerting on HISTCONTROL modifications when combined with other indicators. Focus high-severity alerts on HISTFILE=/dev/null and rm ~/.bash_history which are more clearly malicious. On Windows, Set-PSReadlineOption -HistorySaveStyle SaveNothing is rarely legitimate and should be high-confidence.

Hunting Queries

Hunt for accounts frequently disabling command history. Occasional use may be legitimate, but repeated use across multiple devices is suspicious.

Hunting — KQL

kql

DeviceProcessEvents
| where Timestamp > ago(7d)
| where ProcessCommandLine has_any ("unset HISTFILE", "HISTFILE=/dev/null", "HISTFILESIZE=0", "history -c", "set +o history")
| summarize Count=count(), Devices=dcount(DeviceName) by AccountName
| where Count > 2
| sort by Count desc

Hunting — SPL

spl

index=linux sourcetype=syslog ("unset HISTFILE" OR "HISTFILE=/dev/null" OR "HISTFILESIZE=0" OR "history -c" OR "set +o history")
| stats count, dc(host) as Devices by User
| where count > 2
| sort - count

Atomic Red Team Tests

Test 1 Disable Bash History via HISTFILE

linux

Unsets the HISTFILE environment variable, preventing the current shell session from saving command history to disk. This technique was used by APT38 (BeagleBoyz) and Sea Turtle.

Command

bash

unset HISTFILE && export HISTFILESIZE=0

Cleanup

bash

export HISTFILE=~/.bash_history && export HISTFILESIZE=10000

Expected Telemetry

Auditd execve record for the shell session showing 'unset HISTFILE'. Process creation event in MDE. No bash_history entries will be written for subsequent commands.

Expected Detection

KQL: TamperMethod='HISTFILE Disabled'. SPL: TamperMethod='HISTFILE Disabled'.

Test 2 Redirect History to /dev/null (BPFDoor Pattern)

linux

Redirects both HISTFILE and MYSQL_HISTFILE to /dev/null, matching the exact pattern used by BPFDoor malware to hide shell and database query history.

Command

bash

export HISTFILE=/dev/null && export MYSQL_HISTFILE=/dev/null

Cleanup

bash

export HISTFILE=~/.bash_history && unset MYSQL_HISTFILE

Expected Telemetry

Auditd execve record. The process /proc/<PID>/environ will show HISTFILE=/dev/null.

Expected Detection

KQL: TamperMethod='HISTFILE Disabled'. SPL: TamperMethod='HISTFILE Disabled'.

Test 3 Disable PSReadLine History on Windows

windows

Configures PowerShell PSReadLine to stop saving command history. This prevents commands from being written to ConsoleHost_history.txt.

Command

powershell

powershell.exe -Command "Set-PSReadlineOption -HistorySaveStyle SaveNothing"

Cleanup

powershell

powershell.exe -Command "Set-PSReadlineOption -HistorySaveStyle SaveIncrementally"

Expected Telemetry

Sysmon Event ID 1: powershell.exe with CommandLine containing 'Set-PSReadlineOption'. PowerShell ScriptBlock Log Event ID 4104.

Expected Detection

KQL: TamperMethod='PSReadLine Disabled'. SPL: TamperMethod='PSReadLine Disabled'.

Related Detections

Tactic Hub

TA0112 Defense Impairment ATT&CK Matrix

Related Techniques

T1562 Impair Defenses T1070.003 Clear Command History T1059.004 Unix Shell T1059.001 PowerShell

Detect Impair Command History Logging in IBM QRadar

MITRE ATT&CK

QRadar Detection Query

Data Sources

Required Tables

False Positives & Tuning

Other platforms for T1690

Testing Methodology

Response Playbook

Triage

Containment

Evidence Collection

Escalation Criteria

Investigation Guide

Forensic Artifacts

Tuning Guidance

Hunting Queries

Atomic Red Team Tests

Command

Cleanup

Expected Telemetry

Expected Detection

Command

Cleanup

Expected Telemetry

Expected Detection

Command

Cleanup

Expected Telemetry

Expected Detection

Related Detections

Tactic Hub

Related Techniques

Same Tactic: Defense Impairment

Popular Detections

MITRE ATT&CK

QRadar Detection Query

Data Sources

Required Tables

False Positives & Tuning

Other platforms for T1690

Testing Methodology

Response Playbook

Triage

Containment

Evidence Collection

Escalation Criteria

Investigation Guide

Forensic Artifacts

Tuning Guidance

Hunting Queries

Atomic Red Team Tests

Command

Cleanup

Expected Telemetry

Expected Detection

Command

Cleanup

Expected Telemetry

Expected Detection

Command

Cleanup

Expected Telemetry

Expected Detection

Related Detections

Tactic Hub

Related Techniques

Same Tactic: Defense Impairment

Popular Detections

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