How severe is CVE-2021-28474?

CVE-2021-28474 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-28474 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 51% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-28474?

CVE-2021-28474 primarily affects Microsoft Sharepoint Foundation. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-28474?

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-2021-28474 published?

CVE-2021-28474 was published on 2021-05-11 and last updated on 2026-06-17.

CVE-2021-28474

CVE-2021-28474 is a high-severity vulnerability in Microsoft Sharepoint Foundation with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 51% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-436.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 51% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-436
Affected product: Microsoft Sharepoint Foundation
Published: 2021-05-11
Last modified: 2026-06-17

Description

Microsoft SharePoint Server Remote Code Execution Vulnerability

Frequently asked questions

What is CVE-2021-28474?: Microsoft SharePoint Server Remote Code Execution Vulnerability
How severe is CVE-2021-28474?: CVE-2021-28474 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-28474 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 51% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-28474?: CVE-2021-28474 primarily affects Microsoft Sharepoint Foundation. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-28474?: 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-2021-28474 published?: CVE-2021-28474 was published on 2021-05-11 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:microsoft:sharepoint_foundation:2013:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*

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