CVE-2020-3191: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software IPv6 DNS Denial of Service Vulnerability

Published May 6, 2020
·
Updated

A vulnerability in DNS over IPv6 packet processing for Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to unexpectedly reload, resulting in a denial of service (DoS) condition. The vulnerability is due to improper length validation of a field in an IPv6 DNS packet. An attacker could exploit this vulnerability by sending a crafted DNS query over IPv6, which traverses the affected device. An exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. This vulnerability is specific to DNS over IPv6 traffic only.

Affected Software

83 affected components
Cisco Firepower Threat Defense>=6.2.3<6.2.3.16
Cisco Firepower Threat Defense>=6.3.0<6.3.0.6
Cisco Firepower Threat Defense>=6.4.0<6.4.0.6
Cisco Asa 5505 Firmware=9.4\(1\)
Cisco Asa 5505 Firmware=96.4\(0.42\)
Cisco Asa 5505
Cisco Asa 5510 Firmware=9.4\(1\)
Cisco Asa 5510 Firmware=96.4\(0.42\)
Cisco Asa 5510
Cisco Asa 5512-x Firmware=9.4\(1\)
Cisco Asa 5512-x Firmware=96.4\(0.42\)
Cisco Asa 5512-x
Cisco Asa 5515-x Firmware=9.4\(1\)
Cisco Asa 5515-x Firmware=96.4\(0.42\)
Cisco Asa 5515-x
Cisco Asa 5520 Firmware=9.4\(1\)
Cisco Asa 5520 Firmware=96.4\(0.42\)
Cisco Asa 5520
Cisco Asa 5525-x Firmware=9.4\(1\)
Cisco Asa 5525-x Firmware=96.4\(0.42\)
Cisco Asa 5525-x
Cisco Asa 5540 Firmware=9.4\(1\)
Cisco Asa 5540 Firmware=96.4\(0.42\)
Cisco Asa 5540
Cisco Asa 5545-x Firmware=9.4\(1\)
Cisco Asa 5545-x Firmware=96.4\(0.42\)
Cisco Asa 5545-x
Cisco Asa 5550 Firmware=9.4\(1\)
Cisco Asa 5550 Firmware=96.4\(0.42\)
Cisco Asa 5550
Cisco Asa 5555-x Firmware=9.4\(1\)
Cisco Asa 5555-x Firmware=96.4\(0.42\)
Cisco Asa 5555-x
Cisco Asa 5580 Firmware=9.4\(1\)
Cisco Asa 5580 Firmware=96.4\(0.42\)
Cisco Asa 5580
Cisco Asa 5585-x Firmware=9.4\(1\)
Cisco Asa 5585-x Firmware=96.4\(0.42\)
Cisco Asa 5585-x
Cisco Adaptive Security Appliance Software>=9.6<9.6.4.36
Cisco Adaptive Security Appliance Software>=9.8<9.8.4.12
Cisco Adaptive Security Appliance Software>=9.9<9.9.2.66
Cisco Adaptive Security Appliance Software>=9.10<9.10.1.37
Cisco Adaptive Security Appliance Software>=9.12<9.12.2.9
Cisco Secure Firewall Threat Defense>=6.2.3<6.2.3.16
Cisco Secure Firewall Threat Defense>=6.3.0<6.3.0.6
Cisco Secure Firewall Threat Defense>=6.4.0<6.4.0.6
All of the following
Any of the following
Cisco Asa 5505 Firmware=9.4\(1\)
Cisco Asa 5505 Firmware=96.4\(0.42\)
Cisco Asa 5505
All of the following
Any of the following
Cisco Asa 5510 Firmware=9.4\(1\)
Cisco Asa 5510 Firmware=96.4\(0.42\)
Cisco Asa 5510
All of the following
Any of the following
Cisco Asa 5512-x Firmware=9.4\(1\)
Cisco Asa 5512-x Firmware=96.4\(0.42\)
Cisco Asa 5512-x
All of the following
Any of the following
Cisco Asa 5515-x Firmware=9.4\(1\)
Cisco Asa 5515-x Firmware=96.4\(0.42\)
Cisco Asa 5515-x
All of the following
Any of the following
Cisco Asa 5520 Firmware=9.4\(1\)
Cisco Asa 5520 Firmware=96.4\(0.42\)
Cisco Asa 5520
All of the following
Any of the following
Cisco Asa 5525-x Firmware=9.4\(1\)
Cisco Asa 5525-x Firmware=96.4\(0.42\)
Cisco Asa 5525-x
All of the following
Any of the following
Cisco Asa 5540 Firmware=9.4\(1\)
Cisco Asa 5540 Firmware=96.4\(0.42\)
Cisco Asa 5540
All of the following
Any of the following
Cisco Asa 5545-x Firmware=9.4\(1\)
Cisco Asa 5545-x Firmware=96.4\(0.42\)
Cisco Asa 5545-x
All of the following
Any of the following
Cisco Asa 5550 Firmware=9.4\(1\)
Cisco Asa 5550 Firmware=96.4\(0.42\)
Cisco Asa 5550
All of the following
Any of the following
Cisco Asa 5555-x Firmware=9.4\(1\)
Cisco Asa 5555-x Firmware=96.4\(0.42\)
Cisco Asa 5555-x
All of the following
Any of the following
Cisco Asa 5580 Firmware=9.4\(1\)
Cisco Asa 5580 Firmware=96.4\(0.42\)
Cisco Asa 5580
All of the following
Any of the following
Cisco Asa 5585-x Firmware=9.4\(1\)
Cisco Asa 5585-x Firmware=96.4\(0.42\)
Cisco Asa 5585-x

Event History

May 6, 2020
CVE Published
via MITRE·04:41 PM
Data Sourced
via MITRE·04:41 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·05:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is CVE-2020-3191?

CVE-2020-3191 is a vulnerability in DNS over IPv6 packet processing for Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software.

2

What is the severity of CVE-2020-3191?

The severity of CVE-2020-3191 is high with a CVSS score of 8.6.

3

Which software versions are affected by CVE-2020-3191?

Cisco Adaptive Security Appliance (ASA) Software versions 9.6 to 9.12, and Firepower Threat Defense (FTD) Software versions 6.2.3 to 6.4.0 are affected by CVE-2020-3191.

4

What is the impact of CVE-2020-3191?

CVE-2020-3191 could allow an unauthenticated, remote attacker to cause the device to unexpectedly reload, resulting in a denial of service (DoS) condition.

5

How can I fix CVE-2020-3191?

Cisco has released software updates to address the vulnerability. Please refer to the Cisco Security Advisory for more information.

Contact

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