Medium severity · published Feb 25, 2021
CVE-2021-24099
Skype for Business and Lync Denial of Service Vulnerability
6.5
CVSS
3.2%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.2% · higher than 88% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LS
Lync Server · Microsoft
2013 · source: NVD
SF
Skype For Business Server · Microsoft
2015; 2019 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-24099
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-24099
Patch
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-24099
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