CVE-2021-34527: Windows Print Spooler Remote Code Execution Vulnerability
In CISA’s Known Exploited Vulnerabilities catalog: Microsoft Windows Print Spooler Remote Code Execution Vulnerability.
Added , federal remediation due . Known ransomware use: Known.
Required action: Apply updates per vendor instructions.
Description
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. 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. 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 (Note: 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): HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows NT\Printers\PointAndPrint NoWarningNoElevationOnInstall = 0 (DWORD) or not defined (default setting) UpdatePromptSettings = 0 (DWORD) or not defined (default setting) Having NoWarningNoElevationOnInstall set to 1 makes your system vulnerable by design. 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 KB5005010: Restricting installation of new printer drivers after applying the July 6, 2021 updates. 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.
Vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
Microsoft: Windows 10 Version 1507Microsoft: Windows 10 Version 1607Microsoft: Windows 10 Version 1809Microsoft: Windows 10 Version 20H2Microsoft: Windows 10 Version 21H2Microsoft: Windows 10 Version 22H2Microsoft: Windows 11 version 21H2Microsoft: Windows 11 version 22H2Microsoft: Windows 8.1Microsoft: Windows Server 2008 R2 Service Pack 1Microsoft: Windows Server 2008 R2 Service Pack 1 (Server Core installation)Microsoft: Windows Server 2008 Service Pack 2Microsoft: Windows Server 2008 Service Pack 2 (Server Core installation)Microsoft: Windows Server 2012Microsoft: Windows Server 2012 R2Microsoft: Windows Server 2012 R2 (Server Core installation)Microsoft: Windows Server 2012 (Server Core installation)Microsoft: Windows Server 2016Microsoft: Windows Server 2016 (Server Core installation)Microsoft: Windows Server 2019Microsoft: Windows Server 2019 (Server Core installation)Microsoft: Windows Server 2022Microsoft: Windows Server version 20H2
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34527 (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)