CVE-2021-34471
CVE-2021-34471 is a high-severity vulnerability in Microsoft Malware Protection Engine with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-269.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- CVSS v2: 4.6
- EPSS exploit prediction: 0% (35th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-269
- Affected product: Microsoft Malware Protection Engine
- Published:
- Last modified:
Description
Microsoft Windows Defender Elevation of Privilege Vulnerability
Frequently asked questions
- What is CVE-2021-34471?
- Microsoft Windows Defender Elevation of Privilege Vulnerability
- How severe is CVE-2021-34471?
- CVE-2021-34471 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-34471 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-34471?
- CVE-2021-34471 affects Microsoft Malware Protection Engine. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-34471?
- 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-2021-34471 published?
- CVE-2021-34471 was published on 2021-08-12 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:microsoft:malware_protection_engine:*:*:*:*:*:*:*:*
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