【漏洞預警】微軟Windows列印多工緩衝處理器(Print Spooler)存在安全漏洞(CVE-2021-34527)

[主旨說明:]
【漏洞預警】微軟Windows列印多工緩衝處理器(Print Spooler)存在安全漏洞(CVE-2021-34527),允許攻擊者遠端執行任意程式碼,請儘速確認並進行防護補強!

[內容說明:]
轉發教育機構資安通報應變小組
研究人員發現Windows列印多工緩衝處理器(Print Spooler)服務內之RpcAddPrinterDriverEx函式因未正確限制非授權之存取行為,導致存在安全漏洞(CVE-2021-34527),遠端攻擊者可藉由此漏洞進而執行任意程式碼。

情資分享等級: WHITE(情資內容為可公開揭露之資訊)

[影響平台:]
受影響版本如下:
● Windows 7 for 32-bit Systems Service Pack 1 ● Windows 7 for x64-based Systems Service Pack 1 ● Windows 8.1 for 32-bit systems ● Windows 8.1 for x64-based systems ● Windows RT 8.1 Windows 10 for 32-bit Systems ● Windows 10 for x64-based Systems ● Windows 10 Version 1607 for 32-bit Systems ● Windows 10 Version 1607 for x64-based Systems ● Windows 10 Version 1809 for 32-bit Systems ● Windows 10 Version 1809 for ARM64-based Systems ● Windows 10 Version 1809 for x64-based Systems ● Windows 10 Version 1909 for 32-bit Systems ● Windows 10 Version 1909 for ARM64-based Systems ● Windows 10 Version 1909 for x64-based Systems ● Windows 10 Version 2004 for 32-bit Systems ● Windows 10 Version 2004 for ARM64-based Systems ● Windows 10 Version 2004 for x64-based Systems ● Windows 10 Version 20H2 for 32-bit Systems ● Windows 10 Version 20H2 for ARM64-based Systems ● Windows 10 Version 20H2 for x64-based Systems ● Windows 10 Version 21H1 for 32-bit Systems ● Windows 10 Version 21H1 for ARM64-based Systems ● Windows 10 Version 21H1 for x64-based Systems ● Windows Server 2008 for 32-bit Systems Service Pack 2 ● Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation) ● Windows Server 2008 for x64-based Systems Service Pack 2 ● Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation) ● Windows Server 2008 R2 for x64-based Systems Service Pack 1 ● Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) ● Windows Server 2012 ● Windows Server 2012 (Server Core installation) ● Windows Server 2012 R2 ● Windows Server 2012 R2 (Server Core installation) ● Windows Server 2016 ● Windows Server 2016 (Server Core installation) ● Windows Server 2019 ● Windows Server 2019 (Server Core installation) ● Windows Server, version 1909 (Server Core installation) ● Windows Server, version 2004 (Server Core installation) ● Windows Server, version 20H2 (Server Core Installation)

[建議措施:]
目前微軟官方尚未針對此漏洞釋出更新程式,所有Windows作業系統均受此漏洞影響,請各機關聯絡設備維護廠商或參考以下步驟採取緩解措施,並持續留意更新程式釋出情形:

1.透過網域主機派送群組原則物件(GPO),或在單機電腦上執行「本機群組原則編輯器」(gpedit.msc),將「電腦設定->系統管理範本->印表機->允許列印多工緩衝處理器接受用戶端連線」設為「已停用」。

2.重新開機,或藉由「執行services.msc->在Print Spooler服務上按右鍵->點選重新啟動」以重新啟動Print Spooler服務,以使設定生效。參考網址:https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34527

[參考資料:]
1. https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34527
2. https://www.ithome.com.tw/news/145427
3. https://kb.cert.org/vuls/id/383432
4. https://docs.microsoft.com/zh-tw/troubleshoot/windows-server/printing/use-group-policy-to-control-ad-printer
5. https://thegeekpage.com/how-to-start-stop-or-restart-print-spooler-in-windows-10/