Microsoft Internet Explorer 5.01 SP4, 6 SP1, 6 and 7 on Windows XP SP2 and SP3, 6 and 7 on Windows Server 2003 SP1 and SP2, 7 on Windows Vista Gold and SP1, and 7 on Windows Server 2008 allows remote attackers to execute arbitrary code via a web page that triggers presence of an object in memory that was (1) not properly initialized or (2) deleted, aka "Uninitialized Memory Corruption Vulnerability."
Conclusion & alert: CVE-2009-0554 is rated Moderate Risk (64.5/100): CVSS High severity, with high exploitation likelihood (EPSS 32.17%, 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 | 56.69% | 32.17% | -24.52% |
| 2 | 2025-12-28 | 54.21% | 56.69% | +2.48% |
| 3 | 2025-12-27 | — | 54.21% | — |
Full EPSS history (37 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 8.8 | 3.1 | HIGH |
|
2.8 | 5.9 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| 9.3 | 2.0 | HIGH |
|
8.6 | 10.0 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| microsoft | internet_explorer | 6 | cpe:2.3:a:microsoft:internet_explorer:6:*:*:*:*:*:*:* |
| microsoft | internet_explorer | 7 | cpe:2.3:a:microsoft:internet_explorer:7:*:*:*:*:*:*:* |
| 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:*:*:*:*:*:* |