High severity · published Jun 8, 2021
CVE-2021-26420
Microsoft SharePoint Server Remote Code Execution Vulnerability
7.1
CVSS
3%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.0% · higher than 87% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SH
SharePoint · Microsoft
2019 · source: NVD
SE
Sharepoint Enterprise Server · Microsoft
2016 · source: NVD
SF
Sharepoint Foundation · Microsoft
2013 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-26420
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-26420
Patch
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26420
Third Party Advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-755/
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