Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Authentication Targeted Denial of Service Vulnerability

8.6 CVSS

Vulnerability Description

A vulnerability in the management and VPN web servers of the Remote Access SSL VPN feature of Cisco Secure Firewall ASA Software and Secure FTD Software could allow an unauthenticated, remote attacker to cause the device to unexpectedly stop responding, resulting in a DoS condition. This vulnerability is due to ineffective validation of user-supplied input during the Remote Access SSL VPN authentication process. An attacker could exploit this vulnerability by sending a crafted request to the VPN service on an affected device. A successful exploit could allow the attacker to cause a DoS condition where the device stops responding to Remote Access SSL VPN authentication requests.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-vpn-dos-mfPekA6e

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Affected Vendor

Cisco

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Affected Software

Cisco Adaptive Security Appliance (ASA) Software, Cisco Firepower Threat Defense Software

Vulnerable Versions:

9.12.3, 9.8.3, 9.12.1, 9.12.2, 9.8.2.45, 9.8.4, 9.14.1, 9.12.4, 9.8.2.35, 9.8.2.28, 9.8.2.33, 9.8.2.38, 9.8.4.25, 9.12.3.2, 9.12.3.7, 9.8.3.18, 9.8.3.14, 9.8.4.15, 9.8.4.8, 9.8.3.29, 9.14.1.10, 9.12.2.5, 9.8.4.22, 9.12.3.12, 9.8.4.7, 9.8.4.17, 9.8.3.16, 9.8.4.20, 9.8.3.11, 9.12.1.3, 9.8.4.3, 9.12.2.4, 9.8.4.12, 9.12.1.2, 9.8.3.26, 9.12.2.9, 9.12.3.9, 9.8.3.21, 9.8.4.10, 9.12.2.1, 9.12.4.2, 9.14.1.6, 9.8.3.8, 9.14.1.15, 9.14.1.19, 9.8.4.26, 9.12.4.4, 9.14.1.30, 9.8.4.29, 9.12.4.7, 9.14.2, 9.12.4.8, 9.8.4.32, 9.12.4.10, 9.14.2.4, 9.14.2.8, 9.12.4.13, 9.8.4.33, 9.14.2.13, 9.8.4.34, 9.12.4.18, 9.8.4.35, 9.14.2.15, 9.12.4.24, 9.16.1, 9.8.4.39, 9.14.3, 9.12.4.26, 9.16.1.28, 9.14.3.1, 9.12.4.29, 9.14.3.9, 9.16.2, 9.12.4.30, 9.16.2.3, 9.8.4.40, 9.14.3.11, 9.12.4.35, 9.8.4.41, 9.15.1.1, 9.14.3.13, 9.16.2.7, 9.12.4.37, 9.14.3.15, 9.17.1, 9.16.2.11, 9.14.3.18, 9.16.2.13, 9.12.4.39, 9.12.4.38, 9.8.4.43, 9.14.4, 9.16.2.14, 9.17.1.7, 9.12.4.40, 9.16.3.3, 9.14.4.6, 9.16.3, 9.16.3.14, 9.17.1.9, 9.14.4.7, 9.12.4.41, 9.17.1.10, 9.8.4.44, 9.18.1, 9.12.4.47, 9.14.4.12, 9.16.3.15, 9.18.1.3, 9.17.1.11, 9.12.4.48, 9.14.4.13, 9.18.2, 9.16.3.19, 9.17.1.13, 9.12.4.50, 9.14.4.14, 9.17.1.15, 9.8.4.45, 9.12.4.52, 9.14.4.15, 9.16.3.23, 9.18.2.5, 9.16.4, 9.12.4.54, 9.14.4.17, 9.8.4.46, 9.17.1.20, 9.18.2.7, 9.19.1, 9.16.4.9, 9.12.4.55, 9.18.2.8, 9.14.4.22, 9.16.4.14, 9.8.4.48, 9.18.3, 9.19.1.5, 9.14.4.23, 9.12.4.56, 9.16.4.18, 9.17.1.30, 9.19.1.9, 9.18.3.39, 9.16.4.19, 9.12.4.58, 9.19.1.12, 9.18.3.46, 9.16.4.27, 9.19.1.18, 9.18.3.53, 9.18.3.55, 9.16.4.38, 9.17.1.33, 9.12.4.62, 9.16.4.39, 9.18.3.56, 9.20.1, 9.16.4.42, 9.19.1.22, 9.18.4, 9.20.1.5, 9.18.4.5, 9.19.1.24, 9.16.4.48, 9.18.4.8, 9.20.2, 9.19.1.27, 9.12.4.65, 9.16.4.55, 9.18.4.22, 9.20.2.10, 9.16.4.57, 9.19.1.28, 9.17.1.39, 9.12.4.67, 9.14.4.24, 9.18.4.24, 9.20.2.21, 9.16.4.61, 9.19.1.31, 9.18.4.29, 9.20.2.22, 9.16.4.62, 9.20.3, 9.17.1.45, 9.19.1.37, 9.17.1.46, 9.19.1.38, 6.2.3.14, 6.4.0.1, 6.2.3.7, 6.4.0.2, 6.2.3.9, 6.2.3.1, 6.2.3.2, 6.4.0.5, 6.2.3.10, 6.4.0, 6.4.0.3, 6.2.3.6, 6.4.0.4, 6.2.3.15, 6.2.3.5, 6.2.3.4, 6.2.3.3, 6.2.3.8, 6.4.0.6, 6.2.3.11, 6.2.3.12, 6.2.3.13, 6.4.0.7, 6.4.0.8, 6.6.0, 6.4.0.9, 6.2.3.16, 6.6.0.1, 6.6.1, 6.4.0.10, 6.4.0.11, 6.6.3, 6.6.4, 6.4.0.12, 7.0.0, 6.2.3.17, 7.0.0.1, 6.6.5, 7.0.1, 7.1.0, 6.4.0.13, 6.6.5.1, 6.2.3.18, 7.0.1.1, 6.4.0.14, 7.1.0.1, 6.6.5.2, 7.0.2, 6.4.0.15, 7.2.0, 7.0.2.1, 7.0.3, 6.6.7, 7.1.0.2, 7.2.0.1, 7.0.4, 7.2.1, 7.0.5, 6.4.0.16, 7.3.0, 7.2.2, 7.2.3, 6.6.7.1, 7.3.1, 7.1.0.3, 7.2.4, 7.0.6, 7.2.5, 7.2.4.1, 7.3.1.1, 7.4.0, 6.4.0.17, 7.0.6.1, 7.2.5.1, 7.4.1, 7.2.6, 7.0.6.2, 7.4.1.1, 6.6.7.2, 6.4.0.18, 7.2.7, 7.2.5.2, 7.3.1.2, 7.2.8, 7.4.2, 7.2.8.1, 7.4.2.1