Cisco Adaptive Security Appliances (ASA) 5580 series devices with software before 8.1(2) allow remote attackers to cause a denial of service (IKE process hang) via malformed NAT-T packets, aka Bug ID CSCsr74439.
Conclusion & alert: CVE-2009-4918 is rated Moderate Risk (55.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.39%). 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 | 2026-06-29 | 1.21% | 1.39% | +0.18% |
| 2 | 2026-06-15 | 0.81% | 1.21% | +0.39% |
| 3 | 2026-02-23 | — | 0.81% | — |
Full EPSS history (11 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.8 | 2.0 | HIGH |
|
10.0 | 6.9 | [email protected] |