Buffer overflow in fpcount.exe in IIS 4.0 with FrontPage Server Extensions allows remote attackers to execute arbitrary commands.
Conclusion & alert: CVE-1999-1376 is rated High Risk (69.1/100): CVSS Critical severity, with high exploitation likelihood (EPSS 23.96%, 98th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize 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 | 47.30% | 23.96% | -23.33% |
| 2 | 2025-10-20 | 54.89% | 47.30% | -7.59% |
| 3 | 2025-03-30 | — | 54.89% | — |
Full EPSS history (8 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 10.0 | 2.0 | HIGH |
|
10.0 | 10.0 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| microsoft | internet_information_server | 4.0 | cpe:2.3:a:microsoft:internet_information_server:4.0:*:*:*:*:*:*:* |