8.6
CWE
787 121 20
Advisory Published
Updated

CVE-2021-40118: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Denial of Service Vulnerabilities

First published: Wed Oct 27 2021(Updated: )

A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition. This vulnerability is due to improper input validation when parsing HTTPS requests. An attacker could exploit this vulnerability by sending a malicious HTTPS request to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Credit: ykramarz@cisco.com

Affected SoftwareAffected VersionHow to fix
Cisco Adaptive Security Appliance Software<9.8.4.40
Cisco Secure Firewall Threat Defense<6.4.0.13
Cisco Secure Firewall Threat Defense>=6.5.0<6.6.5
Cisco Secure Firewall Threat Defense>=6.7.0<6.7.0.3
Cisco Secure Firewall Threat Defense>=7.0.0<7.0.1
Cisco Adaptive Security Appliance Software>=9.9.0<9.12.4.29
Cisco Adaptive Security Appliance Software>=9.13.0<9.14.3.9
Cisco Adaptive Security Appliance Software>=9.15.0<9.15.1.17
Cisco Adaptive Security Appliance Software>=9.16.0<9.16.2.3
Cisco ASA 5512-X firmware=009.012\(004.024\)
Cisco ASA 5512-X firmware=009.015\(001\)
Cisco ASA 5512-X firmware=009.015\(001.015\)
Cisco ASA 5512-X firmware=009.015\(001.016\)
Cisco ASA 5512-X firmware=009.016\(001\)
Cisco ASA 5512-X Firmware
Cisco ASA 5505 Firmware=009.012\(004.024\)
Cisco ASA 5505 Firmware=009.015\(001\)
Cisco ASA 5505 Firmware=009.015\(001.015\)
Cisco ASA 5505 Firmware=009.015\(001.016\)
Cisco ASA 5505 Firmware=009.016\(001\)
Cisco ASA 5505 Firmware
Cisco ASA 5515-X Firmware=009.012\(004.024\)
Cisco ASA 5515-X Firmware=009.015\(001\)
Cisco ASA 5515-X Firmware=009.015\(001.015\)
Cisco ASA 5515-X Firmware=009.015\(001.016\)
Cisco ASA 5515-X Firmware=009.016\(001\)
Cisco ASA 5515-X Firmware
Cisco ASA 5525-X Firmware=009.012\(004.024\)
Cisco ASA 5525-X Firmware=009.015\(001\)
Cisco ASA 5525-X Firmware=009.015\(001.015\)
Cisco ASA 5525-X Firmware=009.015\(001.016\)
Cisco ASA 5525-X Firmware=009.016\(001\)
Cisco ASA Software
Cisco ASA 5545-X firmware=009.012\(004.024\)
Cisco ASA 5545-X firmware=009.015\(001\)
Cisco ASA 5545-X firmware=009.015\(001.015\)
Cisco ASA 5545-X firmware=009.015\(001.016\)
Cisco ASA 5545-X firmware=009.016\(001\)
Cisco ASA Software
Cisco ASA 5555-X=009.012\(004.024\)
Cisco ASA 5555-X=009.015\(001\)
Cisco ASA 5555-X=009.015\(001.015\)
Cisco ASA 5555-X=009.015\(001.016\)
Cisco ASA 5555-X=009.016\(001\)
Cisco ASA 5555-X Firmware
Cisco ASA 5580 Firmware=009.012\(004.024\)
Cisco ASA 5580 Firmware=009.015\(001\)
Cisco ASA 5580 Firmware=009.015\(001.015\)
Cisco ASA 5580 Firmware=009.015\(001.016\)
Cisco ASA 5580 Firmware=009.016\(001\)
Cisco ASA 5580 Firmware
Cisco ASA 5585-X=009.012\(004.024\)
Cisco ASA 5585-X=009.015\(001\)
Cisco ASA 5585-X=009.015\(001.015\)
Cisco ASA 5585-X=009.015\(001.016\)
Cisco ASA 5585-X=009.016\(001\)
Cisco ASA 5585-X

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Frequently Asked Questions

  • What is the severity of CVE-2021-40118?

    CVE-2021-40118 has been assigned a CVSS score indicating a high severity risk due to the potential for denial of service.

  • Who is affected by CVE-2021-40118?

    CVE-2021-40118 affects users running vulnerable versions of Cisco Adaptive Security Appliance Software and Cisco Firepower Threat Defense Software.

  • How do I fix CVE-2021-40118?

    To fix CVE-2021-40118, users should update to the latest patched versions of the affected Cisco software.

  • What type of vulnerability is CVE-2021-40118?

    CVE-2021-40118 is classified as a denial of service (DoS) vulnerability that can be exploited by unauthenticated remote attackers.

  • Can CVE-2021-40118 be exploited remotely?

    Yes, CVE-2021-40118 can be exploited remotely by unauthenticated attackers to cause a denial of service condition.

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