Remote code execution in Microsoft Windows Print Spooler

Published: 2021-07-02 | Updated: 2022-09-06
Risk Critical
Patch available YES
Number of vulnerabilities 1
CVE-ID CVE-2021-34527
Exploitation vector Network
Public exploit This vulnerability is being exploited in the wild.
Vulnerable software
Operating systems & Components / Operating system

Windows Server
Operating systems & Components / Operating system

Vendor Microsoft

Security Bulletin

This security bulletin contains information about 1 vulnerabilities.

Updated: 07.07.2021

Changed bulletin status to patched.

1) Code Injection

EUVDB-ID: #VU53886

Risk: Critical


CVE-ID: CVE-2021-34527

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

Exploit availability: Yes


The vulnerability allows a remote user to execute arbitrary code on the target system.

The vulnerability exists due to improper input validation within the RpcAddPrinterDriverEx() function. A remote user can send a specially crafted request to the Windows Print Spooler and execute arbitrary code with SYSTEM privileges.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Note, the vulnerability is being considered a zero-day and dubbed PrintNightmare. This is a different vulnerability than #VU54508 (CVE-2021-1675).


Install update from vendor's website.

Vulnerable software versions

Windows: 7 - 10 S

Windows Server: 2008 - 2019 2004

CPE2.3 External links

Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?