Skype for Business
CVE-2021-24073 — Skype for Business and Lync Spoofing Vulnerability
Executive Summary
None
Overview
6.5
CVSS MEDIUM
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
CVSS Vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:L/A:N/E:P/RL:O/RC:C
ATTACK VECTOR
Network
ATTACK COMPLEXITY
High
PRIVILEGES REQUIRED
Low
USER INTERACTION
Required
SCOPE
Changed
CONFIDENTIALITY
High
INTEGRITY
Low
AVAILABILITY
None
EXPLOIT CODE MATURITY
Proof-of-Concept
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 5.9
EPSS Score
0.0162
probability of exploitation in the next 30 days
0.7395 percentile - updated 2026-08-14
View on FIRST.org
Affected Products
2 affected products
| Product | KB Article | Severity | Impact | Restart Required |
|---|---|---|---|---|
| Microsoft Lync Server 2013 | 5000688 (Security Update) |
Important | Spoofing | Maybe |
| Skype for Business Server 2015 CU 8 | 5000688 (Security Update) |
Important | Spoofing | Maybe |
Patches
1 patch
| Article | Type | Restart |
|---|---|---|
5000688 |
Security Update | Maybe |
Exploits & PoC
No public exploit or PoC has been linked for this CVE yet. When available, references are sourced from public repositories and may be unverified or non-functional — review carefully before use.
Detection Rules
No public Sigma or Nuclei detection rule has been mapped to this CVE yet. Coverage is concentrated on exploited / high-profile vulnerabilities; check SigmaHQ for updates.
Acknowledgments
Anonymous working with the Responsible Disclosure program of de Volksbank
Amit Avrahamov @avr4mit
References
On This Page