msnmsgr.exe in Windows Live Messenger (WLM) 2009 build 14.0.8064.206, and other 14.0.8064.x builds, allows remote attackers to cause a denial of service (application crash) via a modified header in a packet, as possibly demonstrated by a UTF-8.0 value of the charset field in the Content-Type header line. NOTE: this has been reported as a format string vulnerability by some sources, but the provenance of that information is unknown.
Conclusion & alert: CVE-2009-0647 is rated Moderate Risk (52.6/100): CVSS Medium severity, with high exploitation likelihood (EPSS 17.36%, 97th 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 | 18.58% | 17.36% | -1.21% |
| 2 | 2025-03-30 | 18.86% | 18.58% | -0.28% |
| 3 | 2025-03-29 | — | 18.86% | — |
Full EPSS history (15 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| microsoft | windows_live_messenger | 2009 | cpe:2.3:a:microsoft:windows_live_messenger:2009:*:*:*:*:*:*:* |