CVE-2021-26418
CVE-2021-26418 is a medium-severity vulnerability in Microsoft Sharepoint Foundation with a CVSS 3.x base score of 4.6. 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: Medium (CVSS 3.x base score 4.6)
- CVSS v2: 5.8
- EPSS exploit prediction: 1% (66th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-290
- Affected product: Microsoft Sharepoint Foundation
- Published:
- Last modified:
Description
Microsoft SharePoint Server Spoofing Vulnerability
Frequently asked questions
- What is CVE-2021-26418?
- Microsoft SharePoint Server Spoofing Vulnerability
- How severe is CVE-2021-26418?
- CVE-2021-26418 has a CVSS 3.x base score of 4.6, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2021-26418 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-26418?
- CVE-2021-26418 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-2021-26418?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-26418 published?
- CVE-2021-26418 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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