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TI-2021-06369 Aliases CVE-2021-24073GHSA-6w2g-frp4-gwrv

Skype for Business and Lync Spoofing Vulnerability

Priority LOW 35Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

Skype for Business and Lync Spoofing Vulnerability

Why it matters now

EPSS 0.01797 78th percentileScored 2026-11-07
Fix Fixed Skype for Business Server 2015 CU 8 (Microsoft): publicationMicrosoft Lync Server 2013 (Microsoft): publication

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftSkype for Business Server 2015 CU 82015 CU 8 to before publicationpublicationPatch availableCNA
MicrosoftMicrosoft Lync Server 2013before publicationpublicationPatch availableCNA
  • Skype for Business Server 2015 CU 8 VendorMicrosoft Affected 2015 CU 8 to before publication Fixed in publication Patch available CNA
  • Microsoft Lync Server 2013 VendorMicrosoft Affected before publication Fixed in publication Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:microsoft:lync_server:2013:*:*:*:*:*:*:*2013VulnerableMicrosoft
cpe:2.3:a:microsoft:skype_for_business_server:2015:cu8:*:*:*:*:*:*2015 cu8VulnerableMicrosoft
  • cpe:2.3:a:microsoft:lync_server:2013:*:*:*:*:*:*:* Versions 2013 Vulnerable ·Microsoft
  • cpe:2.3:a:microsoft:skype_for_business_server:2015:cu8:*:*:*:*:*:* Versions 2015 cu8 Vulnerable ·Microsoft

Remediation

  • Fix · CNA Skype for Business Server 2015 CU 8 (Microsoft) Fixed in publication
  • Fix · CNA Microsoft Lync Server 2013 (Microsoft) Fixed in publication

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-24073
  2. 2026-10-03 Alias added: GHSA-6w2g-frp4-gwrv

References

Patch 1

  • TI-2013-01140 Microsoft Communicator 2007 R2, Lync 2010, Lync 2010 Attendee, and Lync Server 2013 do… CVSS 2.0HIGH 9.3
  • TI-2014-01426 Cross-site scripting (XSS) vulnerability in the Web Components Server in Microsoft Lync… CVSS 2.0MEDIUM 4.3
  • TI-2014-03321 The Server in Microsoft Lync Server 2013 allows remote attackers to cause a denial of… CVSS 2.0MEDIUM 5.0
  • TI-2014-03319 The Response Group Service in Microsoft Lync Server 2010 and 2013 and the Core Components… CVSS 2.0MEDIUM 5.0
  • TI-2022-14751 Skype for Business and Lync Remote Code Execution Vulnerability CVSS 3.1HIGH 7.2
  • TI-2021-08239 Skype for Business and Lync Remote Code Execution Vulnerability CVSS 3.1HIGH 7.2
See all 15 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences