Heap-based buffer overflow in Microsoft Remote Desktop Connection (formerly Terminal Services Client) running RDP 5.0 through 6.1 on Windows, and Remote Desktop Connection Client for Mac 2.0, allows remote attackers to execute arbitrary code via unspecified parameters, aka "Remote Desktop Connection Heap Overflow Vulnerability."
Conclusion & alert: CVE-2009-1133 is rated High Risk (67.7/100): CVSS Critical severity, with high exploitation likelihood (EPSS 67.06%, 99th 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 | 2026-02-28 | 71.09% | 67.06% | -4.03% |
| 2 | 2026-01-01 | 70.04% | 71.09% | +1.05% |
| 3 | 2025-12-28 | — | 70.04% | — |
Full EPSS history (35 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 9.3 | 2.0 | HIGH |
|
8.6 | 10.0 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| microsoft | windows_2000 | — | cpe:2.3:o:microsoft:windows_2000:-:sp4:*:*:*:*:*:* |
| microsoft | windows_server | 2003 | cpe:2.3:o:microsoft:windows_server:2003:sp2:*:*:*:*:*:* |
| microsoft | windows_server_2003 | — | cpe:2.3:o:microsoft:windows_server_2003:*:sp2:*:*:*:*:*:* |
| microsoft | windows_server_2008 | — | cpe:2.3:o:microsoft:windows_server_2008:*:*:itanium:*:*:*:*:* |
| microsoft | windows_server_2008 | — | cpe:2.3:o:microsoft:windows_server_2008:*:*:x64:*:*:*:*:* |
| microsoft | windows_server_2008 | — | cpe:2.3:o:microsoft:windows_server_2008:*:sp2:itanium:*:*:*:*:* |
| microsoft | windows_server_2008 | — | cpe:2.3:o:microsoft:windows_server_2008:-:-:x32:*:*:*:*:* |
| microsoft | windows_server_2008 | — | cpe:2.3:o:microsoft:windows_server_2008:-:sp2:x64:*:*:*:*:* |
| microsoft | windows_vista | — | cpe:2.3:o:microsoft:windows_vista:*:*:*:*:*:*:*:* |
| microsoft | windows_vista | — | cpe:2.3:o:microsoft:windows_vista:*:*:x64:*:*:*:*:* |
| microsoft | windows_vista | — | cpe:2.3:o:microsoft:windows_vista:*:sp1:*:*:*:*:*:* |
| microsoft | windows_vista | — | cpe:2.3:o:microsoft:windows_vista:*:sp2:*:*:*:*:*:* |
| microsoft | windows_vista | — | cpe:2.3:o:microsoft:windows_vista:-:sp1:*:*:*:*:*:* |
| microsoft | windows_vista | — | cpe:2.3:o:microsoft:windows_vista:-:sp2:*:*:*:*:*:* |
| microsoft | windows_xp | — | cpe:2.3:o:microsoft:windows_xp:*:sp2:pro_x64:*:*:*:*:* |
| microsoft | windows_xp | — | cpe:2.3:o:microsoft:windows_xp:-:sp2:*:*:*:*:*:* |
| microsoft | windows_xp | — | cpe:2.3:o:microsoft:windows_xp:-:sp3:*:*:*:*:*:* |