The setRequestHeader method of the XMLHttpRequest object in Microsoft Internet Explorer 5.01, 6, and 7 does not block dangerous HTTP request headers when certain 8-bit character sequences are appended to a header name, which allows remote attackers to (1) conduct HTTP request splitting and HTTP request smuggling attacks via an incorrect Content-Length header, (2) access arbitrary virtual hosts via a modified Host header, (3) bypass referrer restrictions via an incorrect Referer header, and (4) bypass the same-origin policy and obtain sensitive information via a crafted request header.
Conclusion & alert: CVE-2008-1544 is rated Moderate Risk (57.6/100): CVSS High severity, with high exploitation likelihood (EPSS 26.32%, 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 | 51.21% | 26.32% | -24.89% |
| 2 | 2025-12-28 | 50.19% | 51.21% | +1.01% |
| 3 | 2025-12-27 | — | 50.19% | — |
Full EPSS history (29 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.1 | 2.0 | HIGH |
|
8.6 | 6.9 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| microsoft | internet_explorer | 5.01 | cpe:2.3:a:microsoft:internet_explorer:5.01:sp4:*:*:*:*:*:* |
| microsoft | internet_explorer | 6 | cpe:2.3:a:microsoft:internet_explorer:6:sp1:*:*:*:*:*:* |
| microsoft | internet_explorer | 6 | cpe:2.3:a:microsoft:internet_explorer:6:*:*:*:*:*:*:* |
| microsoft | internet_explorer | 7 | cpe:2.3:a:microsoft:internet_explorer:7:*:*:*:*:*:*:* |