Cisco Adaptive Security Appliance (ASA) 软件和 Firepower Threat Defense (FTD) 软件的 DNS 检查处理程序中存在漏洞，可能允许未经身份验证的远程攻击者对受影响设备造成拒绝服务 (DoS) 攻击。此漏洞是由于对传入请求的处理不当造成的。攻击者可以通过向受影响设备发送大量精心制作的 DNS 请求来利用此漏洞。成功利用此漏洞可能会导致攻击者使设备停止响应，从而造成 DoS 攻击。

😨 **漏洞概述：** Cisco ASA 和 FTD 软件的 DNS 检查处理程序中存在漏洞，可能允许未经身份验证的远程攻击者对受影响设备造成拒绝服务 (DoS) 攻击。此漏洞是由于对传入请求的处理不当造成的。攻击者可以通过向受影响设备发送大量精心制作的 DNS 请求来利用此漏洞。

😨 **攻击方式：** 攻击者可以通过发送大量精心制作的 DNS 请求来利用此漏洞，这些请求会导致设备停止响应，从而造成 DoS 攻击。

😨 **影响：** 成功利用此漏洞可能会导致攻击者使设备停止响应，从而造成 DoS 攻击。

😨 **解决方案：** Cisco 已发布软件更新来解决此漏洞。没有解决此漏洞的变通方法。

😨 **安全影响等级：** 高

A vulnerability in the DNS inspection handler of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service condition (DoS) on an affected device.

This vulnerability is due to a lack of proper processing of incoming requests. An attacker could exploit this vulnerability by sending crafted DNS requests at a high rate to an affected device. A successful exploit could allow the attacker to cause the device to stop responding, resulting in a DoS condition. 

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-dos-nJVAwOeq

This advisory is part of the April 2022 release of the Cisco ASA, FTD, and FMC Security Advisory Bundled publication. For a complete list of the advisories and links to them, see Cisco Event Response: April 2022 Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication.

Security Impact Rating: High
CVE: CVE-2022-20760