CVE-2021-34527

KEV
Published: Lug 02, 2021 Last Modified: Nov 06, 2025
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 8,8
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: none
Scope: unchanged
Confidentiality: high
Integrity: high
Availability: high
HIGH 9,0
Source: [email protected]
Access Vector: network
Access Complexity: low
Authentication: single
Confidentiality: complete
Integrity: complete
Availability: complete

Description

AI Translation Available

<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>

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,9427
Percentile
1,0th
Updated

EPSS Score Trend (Last 90 Days)

Operating System

Windows Server 2022 by Microsoft

Product Information
Vendor Microsoft
Product Windows Server 2022
Version Range Affected
To 10.0.20348.230 (exclusive)
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 11 21H2 by Microsoft

Product Information
Vendor Microsoft
Product Windows 11 21H2
Version Range Affected
To 10.0.22000.318 (exclusive)
cpe:2.3:o:microsoft:windows_11_21h2:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 1607 by Microsoft

Product Information
Vendor Microsoft
Product Windows 10 1607
Version Range Affected
To 10.0.14393.4470 (exclusive)
cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 20H2 by Microsoft

Product Information
Vendor Microsoft
Product Windows 10 20H2
Version Range Affected
To 10.0.19042.1083 (exclusive)
cpe:2.3:o:microsoft:windows_10_20h2:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 21H2 by Microsoft

Product Information
Vendor Microsoft
Product Windows 10 21H2
Version Range Affected
To 10.0.19044.1415 (exclusive)
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 20H2 by Microsoft

Product Information
Vendor Microsoft
Product Windows Server 20H2
Version Range Affected
To 10.0.19042.1083 (exclusive)
cpe:2.3:o:microsoft:windows_server_20h2:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2008 by Microsoft

Product Information
Vendor Microsoft
Product Windows Server 2008
Version -
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 22H2 by Microsoft

Product Information
Vendor Microsoft
Product Windows 10 22H2
Version Range Affected
To 10.0.19045.2251 (exclusive)
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2019 by Microsoft

Product Information
Vendor Microsoft
Product Windows Server 2019
Version Range Affected
To 10.0.17763.2029 (exclusive)
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 1507 by Microsoft

Product Information
Vendor Microsoft
Product Windows 10 1507
Version Range Affected
To 10.0.10240.18969 (exclusive)
cpe:2.3:o:microsoft:windows_10_1507:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 11 22H2 by Microsoft

Product Information
Vendor Microsoft
Product Windows 11 22H2
Version Range Affected
To 10.0.22621.674 (exclusive)
cpe:2.3:o:microsoft:windows_11_22h2:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2012 by Microsoft

Product Information
Vendor Microsoft
Product Windows Server 2012
Version -
cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2008 by Microsoft

Product Information
Vendor Microsoft
Product Windows Server 2008
Version r2
cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 10 1809 by Microsoft

Product Information
Vendor Microsoft
Product Windows 10 1809
Version Range Affected
To 10.0.17763.2029 (exclusive)
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 7 by Microsoft

Product Information
Vendor Microsoft
Product Windows 7
Version -
cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Rt 8.1 by Microsoft

Product Information
Vendor Microsoft
Product Windows Rt 8.1
Version -
cpe:2.3:o:microsoft:windows_rt_8.1:-:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2012 by Microsoft

Product Information
Vendor Microsoft
Product Windows Server 2012
Version r2
cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows Server 2016 by Microsoft

Product Information
Vendor Microsoft
Product Windows Server 2016
Version Range Affected
To 10.0.14393.4470 (exclusive)
cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System

Windows 8.1 by Microsoft

Product Information
Vendor Microsoft
Product Windows 8.1
Version -
cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
https://www.cisa.gov/known-exploited-vulnerabilities-catalo…
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021…
http://packetstormsecurity.com/files/167261/Print-Spooler-R…
http://packetstormsecurity.com/files/167261/Print-Spooler-Remote-DLL-Injection.…
https://portal.msrc.microsoft.com/en-US/security-guidance/a…
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-345…
https://www.kb.cert.org/vuls/id/383432
https://www.kb.cert.org/vuls/id/383432
https://www.vicarius.io/vsociety/posts/cve-2021-34527-print…
https://www.vicarius.io/vsociety/posts/cve-2021-34527-printnightmare-detection-…
https://www.vicarius.io/vsociety/posts/cve-2021-34527-print…
https://www.vicarius.io/vsociety/posts/cve-2021-34527-printnightmare-mitigation…
http://packetstormsecurity.com/files/167261/Print-Spooler-R…
http://packetstormsecurity.com/files/167261/Print-Spooler-Remote-DLL-Injection.…
https://portal.msrc.microsoft.com/en-US/security-guidance/a…
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-345…