CVE-2021-26421 json
Skype for Business and Lync Spoofing Vulnerability
published 2021-05-11 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-13227
- cvss
- 7.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.4%
- EPSS 1.4% chance of exploitation in 30 days, percentile 72%
- public exploits
- 0
- none known
Summary
Skype for Business and Lync Spoofing Vulnerability
Patch / fix
- Microsoft Skype for Business Server 2015 CU11 2046.369
- Microsoft Microsoft Lync Server 2013 CU10 8308.1144
Exploit prediction
1.41% chance of exploitation in the next 30 days, higher than 72% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:L/A:N/E:U/RL:O/RC:C |
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:L/A:N |
| CNA | 3.1 | 7.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N |
| NVD | 2.0 | 5.8 | AV:N/AC:M/Au:N/C:P/I:P/A:N |
Affected products
- Microsoft Skype for Business Server 2015 CU11
- Microsoft Microsoft Lync Server 2013 CU10
References
-
portal.msrc.microsoft.com
/en-US/security-guidance/advisory/CVE-2021-26421
patch, vendor-advisory
Sources
- CVE List CVE-2021-26421
- NVD CVE-2021-26421
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