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Microsoft Defender Antivirus

TMA-DEFENDER-1.15.1

Ensure 'Specify threat alert levels at which default action should not be taken when detected' is set to 'Enabled'

中レベル 1自動defender

説明

This policy setting configures which automatic remediation action Microsoft Defender Antivirus will take for each threat alert level detection. The recommended state for this setting is: Enabled. Rationale: By default, Defender uses the action embedded in each threat’s malware signature (clean, quarantine, remove, etc.). Configuring this setting ensures the same action is always taken, regardless of how Microsoft classifies a specific threat. Audit reads the Group Policy registry value and prints 'compliant', 'unset' (policy not configured, reported as FAIL) or the non-compliant value. Registry value: HKLM\SOFTWARE\Policies\Microsoft\Windows Defender\Threats:Threats_ThreatSeverityDefaultAction (REG_DWORD); compliant when it is 1. Remediation writes 1 locally; in a domain set it through the ADMX so Group Policy does not revert it.

チェック方法

監査方法: Windows レジストリ

registry
$v = (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender\Threats' -Name 'Threats_ThreatSeverityDefaultAction' -ErrorAction SilentlyContinue).'Threats_ThreatSeverityDefaultAction'; if ($null -eq $v) { 'unset' } elseif (($null -ne $v -and @(1) -contains [int64]$v)) { 'compliant' } else { "non-compliant: $v" }
期待される出力
compliant

修正方法

修正方法: シェルコマンド

shell
$p = 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender\Threats'; if (-not (Test-Path -Path $p)) { New-Item -Path $p -Force | Out-Null }; New-ItemProperty -Path $p -Name 'Threats_ThreatSeverityDefaultAction' -Value 1 -PropertyType DWord -Force | Out-Null

プロパティ

オペレーティングシステム
すべて
タグ
defenderantiviruscis-l1
参照
CIS Microsoft Defender Antivirus Benchmark v1.0.0 - 1.15.1 Ensure 'Specify threat alert levels at which default action should not be taken when detected' is set to 'Enabled'

このホストをチェック

監査が許可されているマシンで実行してください。スキャンは読み取り専用です。

shell
tmaegis scan --target defender