CVE-2021-42320
CVE-2021-42320 is a high-severity vulnerability in Microsoft Sharepoint Enterprise Server with a CVSS 3.x base score of 8.0. 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-290.
Key facts
- Severity: High (CVSS 3.x base score 8.0)
- CVSS v2: 3.5
- EPSS exploit prediction: 2% (71st percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-290
- Affected product: Microsoft Sharepoint Enterprise Server
- Published:
- Last modified:
Description
Microsoft SharePoint Server Spoofing Vulnerability
Frequently asked questions
- What is CVE-2021-42320?
- Microsoft SharePoint Server Spoofing Vulnerability
- How severe is CVE-2021-42320?
- CVE-2021-42320 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-42320 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-42320?
- CVE-2021-42320 primarily affects Microsoft Sharepoint Enterprise Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-42320?
- 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-2021-42320 published?
- CVE-2021-42320 was published on 2021-12-15 and last updated on 2026-06-17.
References
Affected products (3)
- cpe:2.3:a:microsoft:sharepoint_enterprise_server:2016:*:*:*:*:*:*:*
- cpe:2.3:a:microsoft:sharepoint_server:-:*:*:*:subscription:*:*:*
- cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*
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