Some Microsoft technologies as used in Windows 8 through 11 allow a temporary client-side performance degradation during processing of multiple Unicode combining characters, aka a "Zalgo text" attack. NOTE: third parties dispute whether the computational cost of interpreting Unicode data should be considered a vulnerability.
Conclusion & alert: CVE-2017-20190 is rated Low Risk (15.1/100): low exploitation likelihood (EPSS 0.06%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.
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 | 2025-03-17 | 0.04% | 0.06% | +0.01% |
| 2 | 2024-03-27 | — | 0.04% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
No CVSS data in dataset for this CVE.
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| No affected products in dataset. | |||