Medium severity · published Jul 16, 2021
CVE-2021-34451
Microsoft Office Online Server Spoofing Vulnerability
5.3
CVSS
1.8%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.8% · higher than 78% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OO
Office Online Server · Microsoft
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-34451
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-34451
msrc.microsoft.com
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34451
Patch
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34451
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