Schannel in Microsoft Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8, Windows 8.1, Windows Server 2012 Gold and R2, and Windows RT Gold and 8.1 does not properly restrict Diffie-Hellman Ephemeral (DHE) key lengths, which makes it easier for remote attackers to defeat cryptographic protection mechanisms via unspecified vectors, aka "Schannel Information Disclosure Vulnerability."
Conclusion & alert: CVE-2015-1716 is rated Moderate Risk (55.6/100): CVSS Medium severity, with high exploitation likelihood (EPSS 18.43%, 95th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +2.38% over the last day, indicating growing attacker interest. 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 | 2025-12-28 | 16.05% | 18.43% | +2.38% |
| 2 | 2025-12-27 | 18.43% | 16.05% | -2.38% |
| 3 | 2025-10-28 | — | 18.43% | — |
Full EPSS history (16 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_7 | — | cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:*:*:*:* |
| microsoft | windows_8 | — | cpe:2.3:o:microsoft:windows_8:-:*:*:*:*:*:*:* |
| microsoft | windows_8.1 | — | cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:*:* |
| microsoft | windows_rt | — | cpe:2.3:o:microsoft:windows_rt:-:*:*:*:*:*:*:* |
| microsoft | windows_rt_8.1 | — | cpe:2.3:o:microsoft:windows_rt_8.1:-:*:*:*:*:*:*:* |
| 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:-:sp2:*:*:*:*:*:* |
| microsoft | windows_server_2008 | r2 | cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:itanium:* |
| microsoft | windows_server_2008 | r2 | cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:* |
| microsoft | windows_server_2012 | — | cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:* |
| microsoft | windows_server_2012 | r2 | cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:* |
| microsoft | windows_vista | — | cpe:2.3:o:microsoft:windows_vista:-:sp2:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| http://www.securityfocus.com/bid/74489 | Third Party Advisory VDB Entry |
| http://www.securitytracker.com/id/1032283 | Third Party Advisory VDB Entry |
| https://docs.microsoft.com/en-us/security-updates/securitybulletins/2015/ms15-055 | Patch Vendor Advisory |