Go to homepageCyberStrike

Menu

Star on GitHub · 3.3k
Sign inDownload

CVE-2021-34527

8.8 · HIGHActively Exploited

A remote code execution vulnerability exists when the Windows Print Spooler service improperly performs privileged file operations.

Published Jul 2, 2021EPSS 99.79%

Overview

CVE-2021-34527 is a high-severity vulnerability. It was published on July 2, 2021 and has a CVSS 3.1 base score of 8.8 (HIGH). This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild.

This vulnerability has a CVSS 3.1 base score of 8.8, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.

Technical 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

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References

Refmsrc.microsoft.com/update-guide/vulnerability/CVE-2021-34527Refpacketstormsecurity.com/files/167261/Print-Spooler-Remote-DLL-Injection.htmlRefportal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34527Refwww.kb.cert.org/vuls/id/383432Refwww.vicarius.io/vsociety/posts/cve-2021-34527-printnightmare-detection-scriptRefwww.vicarius.io/vsociety/posts/cve-2021-34527-printnightmare-mitigation-scriptCISAwww.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-34527

How CyberStrike helps

Frequently asked questions

What is CVE-2021-34527?

CVE-2021-34527 is a high-severity vulnerability. It was published on July 2, 2021 and has a CVSS 3.1 base score of 8.8 (HIGH). This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild.

How severe is CVE-2021-34527?

This vulnerability has a CVSS 3.1 base score of 8.8, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.

How do I fix or remediate CVE-2021-34527?

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

How can CyberStrike help with CVE-2021-34527?

CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2021-34527 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.

Related HIGH CVEs from 2021

View all
Browse by year2026202520242023202220212020201920182017201620152014201320122011201020092008200720062005200420032002200120001999
LiveWatch live →