Cisco Identity Services Engine does not properly restrict the creation of guest accounts, which allows remote attackers to cause a denial of service (exhaustion of the account supply) via a series of requests within one session, aka Bug ID CSCue94287.
Conclusion & alert: CVE-2013-5521 is rated Moderate Risk (43.5/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.23%). 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 | 0.47% | 1.23% | +0.76% |
| 2 | 2025-03-17 | 0.15% | 0.47% | +0.32% |
| 3 | 2024-09-17 | — | 0.15% | — |
Full EPSS history (6 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 |
|---|---|---|---|
| cisco | identity_services_engine_software | — | cpe:2.3:a:cisco:identity_services_engine_software:-:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| http://tools.cisco.com/security/center/content/CiscoSecurityNotice/CVE-2013-5521 | Vendor Advisory |