A vulnerability in the email filtering functionality of Cisco AsyncOS Software for Cisco Email Security Appliances could allow an unauthenticated, remote attacker to bypass Advanced Malware Protection (AMP) filters that are configured for an affected device. This vulnerability affects all releases prior to the first fixed release of Cisco AsyncOS Software for both virtual and hardware versions of Cisco Email Security Appliances, if the AMP feature is configured to scan incoming email attachments. More Information: CSCuz85823. Known Affected Releases: 10.0.0-082 9.7.0-125 9.7.1-066. Known Fixed Releases: 10.0.0-203 9.7.2-131.
Conclusion & alert: CVE-2016-6463 is rated Moderate Risk (43.9/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.13%). Mandatory action: Review affected assets and schedule 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 | 0.18% | 1.13% | +0.95% |
| 2 | 2025-03-17 | 0.13% | 0.18% | +0.05% |
| 3 | 2023-03-07 | — | 0.13% | — |
Full EPSS history (4 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.3 | 3.0 | MEDIUM |
|
3.9 | 1.4 | [email protected] |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| cisco | email_security_appliance_firmware | 9.7.0-125 | cpe:2.3:o:cisco:email_security_appliance_firmware:9.7.0-125:*:*:*:*:*:*:* |
| cisco | email_security_appliance_firmware | 9.7.1-06 | cpe:2.3:o:cisco:email_security_appliance_firmware:9.7.1-06:*:*:*:*:*:*:* |
| cisco | email_security_appliance_firmware | 10.0.0-082 | cpe:2.3:o:cisco:email_security_appliance_firmware:10.0.0-082:*:*:*:*:*:*:* |