CVE-2021-33436
CVE-2021-33436 is a high-severity vulnerability in Nomachine with a CVSS 3.x base score of 7.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 7.3)
- CVSS v2: 6.2
- EPSS exploit prediction: 0% (19th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Nomachine
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2021-33436?
- 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.
- How severe is CVE-2021-33436?
- CVE-2021-33436 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-33436 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-33436?
- CVE-2021-33436 affects Nomachine. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-33436?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-33436 published?
- CVE-2021-33436 was published on 2022-04-28 and last updated on 2026-06-17.
References
- https://github.com/active-labs/Advisories/blob/master/2021/ACTIVE-2021-001.md
- https://knowledgebase.nomachine.com/SU05S00223
- https://knowledgebase.nomachine.com/SU05S00224
- https://knowledgebase.nomachine.com/TR05S10236
Affected products (1)
- cpe:2.3:a:nomachine:nomachine:*:*:*:*:*:*:*:*
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