A spoofing vulnerability exists when a Lync Server or Skype for Business Server does not properly sanitize a specially crafted request, aka 'Skype for Business and Lync Spoofing Vulnerability'.
Conclusion & alert: CVE-2019-0798 is rated Moderate Risk (53.3/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 2.08%). Core evidence: EPSS rose +1.23% over the last day, indicating growing attacker interest. Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.85% | 2.08% | +1.23% |
| 2 | 2026-04-03 | 0.46% | 0.85% | +0.39% |
| 3 | 2025-08-02 | — | 0.46% | — |
Full EPSS history (15 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.1 | 3.0 | MEDIUM |
|
2.8 | 2.7 | [email protected] |
| 4.3 | 2.0 | MEDIUM |
|
8.6 | 2.9 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| microsoft | lync_server | 2013 | cpe:2.3:a:microsoft:lync_server:2013:*:*:*:*:*:*:* |
| microsoft | skype_for_business_server | 2015 | cpe:2.3:a:microsoft:skype_for_business_server:2015:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0798 | Patch Vendor Advisory |