# CVE-2021-34527: Microsoft Windows Print Spooler Remote Code Execution Vulnerability

Source: https://junglewise.ai/threats/cve-2021-34527-microsoft-windows-print-spooler-remote-code-execution  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-11-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2021-34527 · Severity: critical · CVSS 8.8 · Exploited in the wild · Published 2021-11-03

The Windows Print Spooler service improperly performs privileged file operations, leading to a remote code execution vulnerability known as PrintNightmare. An authenticated attacker can exploit this to run arbitrary code with SYSTEM privileges, allowing for full system compromise including data manipulation and account creation.

Technologies: [Microsoft Windows](https://junglewise.ai/threats/technologies/windows). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2021-34527 exploited in the wild?** Yes. CVE-2021-34527 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2021-34527?** Critical severity, with a CVSS score of 8.8, published 3 November 2021.

**Which products and versions are affected?** Microsoft Windows Server 2012; Microsoft Windows Server 2016; Microsoft Windows 10 Version 1607; Microsoft Windows Print Spooler service.

**Is there a fix for CVE-2021-34527?** A patch was published on 2021-07-06: Microsoft released initial security updates and KB5005010. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2021-34527 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-2021-34527?** Check whether you run Microsoft Windows. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Microsoft Windows Server 2012
- Microsoft Windows Server 2016
- Microsoft Windows 10 Version 1607
- Microsoft Windows Print Spooler service

## Timeline

- 2021-07-06: patched: Microsoft released initial security updates and KB5005010.
- 2021-07-07: patched: Security updates released for Windows Server 2012, 2016, and Windows 10 v1607.
- 2021-11-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog.
- 2021-11-03: disclosed

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