Spoofing through undisclosed request handling
Published May 11, 2021 · Updated Feb 28, 2025
Spoofing in Microsoft SharePoint Foundation 2013 and SharePoint Server 2016 and 2019 allows remote authenticated users to alter content. Microsoft has not published the affected request-handling component or the incorrect operation performed on untrusted input. Exploitation requires low-privilege access and user interaction and permits limited content disclosure and modification without service interruption.
Summary
What happened
Spoofing in Microsoft SharePoint Foundation 2013 and SharePoint Server 2016 and 2019 allows remote authenticated users to alter content. Microsoft has not published the affected request-handling component or the incorrect operation performed on untrusted input. Exploitation requires low-privilege access and user interaction and permits limited content disclosure and modification without service interruption.
The record
- CVE
- CVE-2021-26418
- Published
- May 11, 2021
- Updated
- Feb 28, 2025
- Vendor
- Microsoft
- Product
- Microsoft SharePoint Foundation 2013
- Classifications
- CWE-290
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- May 11, 2021CVE publishedPublication date reported by the CVE source.
- Feb 28, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=15.0.0 <15.0.5345.1000
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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