<p>A remote code execution vulnerability exists when the Windows Print Spooler service improperly performs privileged file operations. An attacker who successfully exploited this vulnerability could run arbitrary code with SYSTEM privileges. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.</p> <p>UPDATE July 7, 2021: The security update for Windows Server 2012, Windows Server 2016 and Windows 10, Version 1607 have been released. Please see the Security Updates table for the applicable update for your system. We recommend that you install these updates immediately. If you are unable to install these updates, see the FAQ and Workaround sections in this CVE for information on how to help protect your system from this vulnerability.</p> <p>In addition to installing the updates, in order to secure your system, you must confirm that the following registry settings are set to 0 (zero) or are not defined (<strong>Note</strong>: These registry keys do not exist by default, and therefore are already at the secure setting.), also that your Group Policy setting are correct (see FAQ):</p> <ul> <li>HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows NT\Printers\PointAndPrint</li> <li>NoWarningNoElevationOnInstall = 0 (DWORD) or not defined (default setting)</li> <li>UpdatePromptSettings = 0 (DWORD) or not defined (default setting)</li> </ul> <p><strong>Having NoWarningNoElevationOnInstall set to 1 makes your system vulnerable by design.</strong></p> <p>UPDATE July 6, 2021: Microsoft has completed the investigation and has released security updates to address this vulnerability. Please see the Security Updates table for the applicable update for your system. We recommend that you install these updates immediately. If you are unable to install these updates, see the FAQ and Workaround sections in this CVE for information on how to help protect your system from this vulnerability. See also <a href="https://support.microsoft.com/topic/31b91c02-05bc-4ada-a7ea-183b129578a7">KB5005010: Restricting installation of new printer drivers after applying the July 6, 2021 updates</a>.</p> <p>Note that the security updates released on and after July 6, 2021 contain protections for CVE-2021-1675 and the additional remote code execution exploit in the Windows Print Spooler service known as “PrintNightmare”, documented in CVE-2021-34527.</p>
総合評価: CVE-2021-34527 は在野悪用が確認された重大脅威(100/100)。CVSS 深刻度は高。悪用される可能性が高い(EPSS 99.76%、100 パーセンタイル) 根拠: CISA KEV に登録(追加日 2021-11-03)。Microsoft / Windows が対象で、悪用が確認されています。未認証でリモート管理権限を奪取されるリスクが極めて高い。 直近 1 日で EPSS が +5.56% 上昇。悪用への関心が高まっている可能性があります。 推奨対応: CISA の対応期限を過ぎています。緊急のパッチ適用を最優先に検討してください。
リスクは変動します。再評価に基づき、本ページの表示内容を更新しています。
: Microsoft Windows Print Spooler Remote Code Execution Vulnerability · CISA KEV の詳細
: 2021-11-03
: 2022-05-03
: Apply updates per vendor instructions.
| EDB-ID | ソース | 種別 | 公開 | リンク |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ | |
| — | nvd_ref | exploit_tag | Exploit-DB ↗ | |
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS は日次で悪用されやすさの相対度合いを推定します。パーセンタイルは採点済み CVE の中での相対位置(高いほど相対的に深刻)を示します。
| # | 日付 | 旧 EPSS スコア | 新 EPSS スコア | Δ(新 − 旧) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 94.20% | 99.76% | +5.56% |
| 2 | 2026-03-15 | 94.27% | 94.20% | -0.07% |
| 3 | 2025-12-28 | — | 94.27% | — |
EPSS の全履歴 (全 34 件)
この CVE の CVSS 指標。
| ベーススコア | バージョン | 深刻度 | ベクトル | 悪用しやすさ | 影響 | スコアの出典 |
|---|---|---|---|---|---|---|
| 8.8 | 3.1 | HIGH |
|
2.8 | 5.9 | [email protected] |
| 8.8 | 3.1 | HIGH |
|
2.8 | 5.9 | [email protected] |
| 9.0 | 2.0 | HIGH |
|
8.0 | 10.0 | [email protected] |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| microsoft | windows_10_1507 | < 10.0.10240.18969 | cpe:2.3:o:microsoft:windows_10_1507:*:*:*:*:*:*:*:* |
| microsoft | windows_10_1607 | < 10.0.14393.4470 | cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:*:* |
| microsoft | windows_10_1809 | < 10.0.17763.2029 | cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:*:* |
| microsoft | windows_10_20h2 | < 10.0.19042.1083 | cpe:2.3:o:microsoft:windows_10_20h2:*:*:*:*:*:*:*:* |
| microsoft | windows_10_21h2 | < 10.0.19044.1415 | cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:*:* |
| microsoft | windows_10_22h2 | < 10.0.19045.2251 | cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:*:* |
| microsoft | windows_11_21h2 | < 10.0.22000.318 | cpe:2.3:o:microsoft:windows_11_21h2:*:*:*:*:*:*:*:* |
| microsoft | windows_11_22h2 | < 10.0.22621.674 | cpe:2.3:o:microsoft:windows_11_22h2:*:*:*:*:*:*:*:* |
| microsoft | windows_7 | — | cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:*:*:*:* |
| microsoft | windows_8.1 | — | cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:*:* |
| microsoft | windows_rt_8.1 | — | cpe:2.3:o:microsoft:windows_rt_8.1:-:*:*:*:*:*:*:* |
| microsoft | windows_server_2008 | — | cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:* |
| microsoft | windows_server_2008 | r2 | cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:* |
| microsoft | windows_server_2012 | — | cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:* |
| microsoft | windows_server_2012 | r2 | cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:* |
| microsoft | windows_server_2016 | < 10.0.14393.4470 | cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:* |
| microsoft | windows_server_2019 | < 10.0.17763.2029 | cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:* |
| microsoft | windows_server_2022 | < 10.0.20348.230 | cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* |
| microsoft | windows_server_20h2 | < 10.0.19042.1083 | cpe:2.3:o:microsoft:windows_server_20h2:*:*:*:*:*:*:*:* |
| URL | タグ |
|---|---|
| http://packetstormsecurity.com/files/167261/Print-Spooler-Remote-DLL-Injection.html | Exploit Third Party Advisory VDB Entry |
| https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34527 | Mitigation Patch Vendor Advisory |
| https://www.kb.cert.org/vuls/id/383432 | Third Party Advisory US Government Resource |
| https://www.vicarius.io/vsociety/posts/cve-2021-34527-printnightmare-detection-script | Exploit Third Party Advisory |
| https://www.vicarius.io/vsociety/posts/cve-2021-34527-printnightmare-mitigation-script | Exploit Third Party Advisory |
| https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-34527 | US Government Resource |