A vulnerability in the SAML 2.0 single sign-on (SSO) feature of Cisco Secure Firewall ASA Software and Secure FTD Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a DoS condition. This vulnerability is due to insufficient error checking when processing SAML messages. An attacker could exploit this vulnerability by sending crafted SAML messages to the SAML service. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
Conclusion & alert: CVE-2026-20101 is rated Moderate Risk (44.1/100): CVSS High severity, with low exploitation likelihood (EPSS 0.35%). 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 | 0.15% | 0.35% | +0.20% |
| 2 | 2026-04-05 | 0.10% | 0.15% | +0.05% |
| 3 | 2026-03-05 | — | 0.10% | — |
Full EPSS history (3 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 8.6 | 3.1 | HIGH |
|
3.9 | 4.0 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| cisco | adaptive_security_appliance_software | >= 9.12.1, < 9.16.4.85 | cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:* |
| cisco | adaptive_security_appliance_software | >= 9.17.1, < 9.18.4.66 | cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:* |
| cisco | adaptive_security_appliance_software | >= 9.19.1, < 9.20.4 | cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:* |
| cisco | adaptive_security_appliance_software | >= 9.22.1.1, < 9.22.2.4 | cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:* |
| cisco | adaptive_security_appliance_software | >= 9.23.1, < 9.23.1.7 | cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense_software | >= 6.4.0, < 7.0.9 | cpe:2.3:a:cisco:firepower_threat_defense_software:*:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense_software | >= 7.1.0, < 7.2.11 | cpe:2.3:a:cisco:firepower_threat_defense_software:*:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense_software | >= 7.3.0, < 7.4.3 | cpe:2.3:a:cisco:firepower_threat_defense_software:*:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense_software | >= 7.6.0, < 7.6.4 | cpe:2.3:a:cisco:firepower_threat_defense_software:*:*:*:*:*:*:*:* |
| cisco | firepower_threat_defense_software | >= 7.7.0, < 7.7.11 | cpe:2.3:a:cisco:firepower_threat_defense_software:*:*:*:*:*:*:*:* |