cisco-sa-asaftd-dos-4ygzLKU9: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software SSL/TLS Denial of Service Vulnerability

Published Oct 27, 2021
·
Updated

A vulnerability in SSL/TLS message handler for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability exists because incoming SSL/TLS packets are not properly processed. An attacker could exploit this vulnerability by sending a crafted SSL/TLS packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, 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-4ygzLKU9 This advisory is part of the October 2021 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: October 2021 Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication.

Credit

This vulnerability was found by Sanmith Prakash(Cisco during internal security testing)

Affected Software

2 affected componentsFixes available
Cisco ASA Software=9.15, <9.15.1.17, >=9.13, <=9.14, <9.14.3.9, >=9.9, =9.10, <=9.12, <9.12.4.26, >=9.7 and earlier, <=9.8, <9.8.4.40
9.15.1.179.14.3.99.12.4.269.8.4.40
Cisco FTD Software>=6.5.0, =6.6.0, <=6.7.0, <6.7.0.3 (Jan 2022), >=6.3.0, <=6.4.0, <6.4.0.13 (Nov 2021), >=6.2.2 and earlier, <=6.2.3, <6.2.3.17
6.7.0.3 (Jan 2022)6.4.0.13 (Nov 2021)6.2.3.17

Event History

Oct 27, 2021
Advisory Published
via Cisco·04:00 PM

Child vulnerabilities

Contains the following vulnerabilities.

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Frequently Asked Questions

1

What is the vulnerability ID for this Cisco ASA and FTD vulnerability?

The vulnerability ID is cisco-sa-asaftd-dos-4ygzLKU9.

2

What is the severity level of the cisco-sa-asaftd-dos-4ygzLKU9 vulnerability?

The severity level of the cisco-sa-asaftd-dos-4ygzLKU9 vulnerability is high.

3

What is the affected software for the cisco-sa-asaftd-dos-4ygzLKU9 vulnerability?

The affected software for the cisco-sa-asaftd-dos-4ygzLKU9 vulnerability is Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software.

4

How can an unauthenticated, remote attacker exploit the cisco-sa-asaftd-dos-4ygzLKU9 vulnerability?

An unauthenticated, remote attacker can exploit the cisco-sa-asaftd-dos-4ygzLKU9 vulnerability to cause a denial of service (DoS) condition on an affected device.

5

How can I fix the cisco-sa-asaftd-dos-4ygzLKU9 vulnerability?

To fix the cisco-sa-asaftd-dos-4ygzLKU9 vulnerability, upgrade to the recommended software versions provided by Cisco.

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