An information disclosure vulnerability exists when the Microsoft Edge Fetch API incorrectly handles a filtered response type, aka "Microsoft Edge Information Disclosure Vulnerability." This affects Microsoft Edge.
Conclusion & alert: CVE-2018-8366 is rated Low Risk (39.3/100): CVSS Low severity, with high exploitation likelihood (EPSS 5.05%, 91th 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 | 15.61% | 5.05% | -10.57% |
| 2 | 2026-03-30 | 12.19% | 15.61% | +3.42% |
| 3 | 2026-03-01 | — | 12.19% | — |
Full EPSS history (26 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 3.1 | 3.0 | LOW |
|
1.6 | 1.4 | [email protected] |
| 2.6 | 2.0 | LOW |
|
4.9 | 2.9 | [email protected] |
| URL | Tags |
|---|---|
| http://www.securityfocus.com/bid/105253 | Third Party Advisory VDB Entry |
| http://www.securitytracker.com/id/1041623 | Third Party Advisory VDB Entry |
| https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8366 | Patch Vendor Advisory |