CVE-2021-26421

Skype for Business and Lync Spoofing Vulnerability

MEDIUM
6.5
CVSS Score
Published: May 11, 2021 at 07:11 PM UTC
Updated: June 17, 2026 at 03:43 AM UTC
2 products affected across 1 vendorSkype for Business ServerLync Server

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Severity
MEDIUM6.5
Exploit prediction
EPSS 1%

Description

Skype for Business and Lync Spoofing Vulnerability

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

8308.0 ≤ v < 8308.114420132013 cumulative_update_108308.0
Affected range stops below 8308.1144, so it looks safe — our inference, not a vendor statement
2015 CU11 ≤ v < 2046.36920152015 CU112015 cumulative_update_11
Affected range stops below 2046.369, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

6.5MEDIUMmicrosoft
Vector?

Quick Info

StatusMODIFIED
CWE
NVD-CWE-noinfo

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