Microsoft Internet Explorer 8 through 11 mishandles HTML attributes in HTTP responses, which allows remote attackers to bypass a cross-site scripting (XSS) protection mechanism via unspecified vectors, aka "Internet Explorer XSS Filter Bypass Vulnerability."
Conclusion & alert: CVE-2015-6138 is rated Moderate Risk (45.7/100): CVSS Medium severity, with high exploitation likelihood (EPSS 12.40%, 96th 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 | 19.81% | 12.40% | -7.41% |
| 2 | 2026-03-17 | 24.02% | 19.81% | -4.22% |
| 3 | 2025-06-29 | — | 24.02% | — |
Full EPSS history (22 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 4.3 | 2.0 | MEDIUM |
|
8.6 | 2.9 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| microsoft | internet_explorer | 8 | cpe:2.3:a:microsoft:internet_explorer:8:*:*:*:*:*:*:* |
| microsoft | internet_explorer | 9 | cpe:2.3:a:microsoft:internet_explorer:9:*:*:*:*:*:*:* |
| microsoft | internet_explorer | 10 | cpe:2.3:a:microsoft:internet_explorer:10:*:*:*:*:*:*:* |
| microsoft | internet_explorer | 11 | cpe:2.3:a:microsoft:internet_explorer:11:-:*:*:*:*:*:* |