CVE-2021-42298
CVE-2021-42298 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-94.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- CVSS v2: 9.3
- EPSS exploit prediction: 5% (92nd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-94
- Affected product: Microsoft Malware Protection Engine
- Published:
- Last modified:
Description
Microsoft Defender Remote Code Execution Vulnerability
Frequently asked questions
- What is CVE-2021-42298?
- Microsoft Defender Remote Code Execution Vulnerability
- How severe is CVE-2021-42298?
- CVE-2021-42298 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-42298 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-42298?
- CVE-2021-42298 affects Microsoft Malware Protection Engine. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-42298?
- 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-2021-42298 published?
- CVE-2021-42298 was published on 2021-11-10 and last updated on 2026-08-19.
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42298
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42298
Affected products (1)
- cpe:2.3:a:microsoft:malware_protection_engine:*:*:*:*:*:*:*:*
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