CVE-2021-33436

Name: CVE-2021-33436
Creator: NVD / NIST
Published: 2022-04-28T11:15:07.72+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.3/10EPSS 0.27%

Last modified Jun 17, 2026

CVE-2021-33436 is a high-severity vulnerability rated 7.3/10 on the CVSS scale. NoMachine for Windows prior to version 6.15.1 and 7.5.2 suffer from local privilege escalation due to the lack of safe DLL loading. This vulnerability allows local non-privileged users to perform DLL Hijacking via any writable directory listed under the system path and ultimately execute code as NT AUTHORITY\SYSTEM.. EPSS estimates a 0.27% chance of exploitation in the next 30 days.

Description

NoMachine for Windows prior to version 6.15.1 and 7.5.2 suffer from local privilege escalation due to the lack of safe DLL loading. This vulnerability allows local non-privileged users to perform DLL Hijacking via any writable directory listed under the system path and ultimately execute code as NT AUTHORITY\SYSTEM.

Metrics

CVSS 3.1

7.3/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H

EPSS Probability

0.27%

18.5th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Nomachine	Nomachine	>= 6.0.0, < 6.15.1
Nomachine	Nomachine	>= 7.0, < 7.5.2

References

https://github.com/active-labs/Advisories/blob/master/2021/ACTIVE-2021-001.mdThird Party Advisory
https://knowledgebase.nomachine.com/SU05S00223Release Notes, Vendor Advisory
https://knowledgebase.nomachine.com/SU05S00224Release Notes, Vendor Advisory
https://knowledgebase.nomachine.com/TR05S10236Vendor Advisory
https://github.com/active-labs/Advisories/blob/master/2021/ACTIVE-2021-001.mdThird Party Advisory
https://knowledgebase.nomachine.com/SU05S00223Release Notes, Vendor Advisory
https://knowledgebase.nomachine.com/SU05S00224Release Notes, Vendor Advisory
https://knowledgebase.nomachine.com/TR05S10236Vendor Advisory

Timeline

Published: Apr 28, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-33436?

How severe is CVE-2021-33436?

CVE-2021-33436 has a CVSS score of 7.3/10 (HIGH severity). The EPSS model estimates a 0.27% probability of exploitation in the next 30 days.

How do I fix CVE-2021-33436?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-33436?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST