CVE Watch—

CVE-2021-34527

Microsoft Windows Print Spooler Remote Code Execution Vulnerability

CVSS

—

No CVSS

EPSS

99.8%

p100

KEV

YES

Nov 3, 2021

Exploit Today

0-100

Published: — · Last modified: —

EPSS · 30d

99.8%EPSS · 30 days99.8%

2026-06-302026-07-16

KEV catalog record

Product

Microsoft / Windows

Vulnerability

Microsoft Windows Print Spooler Remote Code Execution Vulnerability

Added to KEV

Nov 3, 2021

Remediate by

May 3, 2022

Known ransomware use

Yes

Summary description

Microsoft Windows Print Spooler contains an unspecified vulnerability due to the Windows Print Spooler service improperly performing privileged file operations. Successful exploitation allows an attacker to perform remote code execution with SYSTEM privileges. The vulnerability is also known under the moniker of PrintNightmare.

Required action

Apply updates per vendor instructions.

Notes

Reference CISA's ED 21-04 (https://www.cisa.gov/news-events/directives/ed-21-04-mitigate-windows-print-spooler-service-vulnerability) for further guidance and requirements. Note: The due date for addressing this vulnerability aligns with the requirements outlined in ED 21-04. https://nvd.nist.gov/vuln/detail/CVE-2021-34527

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