CVE-2021-40116: Multiple Cisco Products Snort Rule Denial of Service Vulnerability

Published Oct 27, 2021
·
Updated

Multiple Cisco products are affected by a vulnerability in Snort rules that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.The vulnerability is due to improper handling of the Block with Reset or Interactive Block with Reset actions if a rule is configured without proper constraints. An attacker could exploit this vulnerability by sending a crafted IP packet to the affected device. A successful exploit could allow the attacker to cause through traffic to be dropped. Note: Only products with Snort3 configured and either a rule with Block with Reset or Interactive Block with Reset actions configured are vulnerable. Products configured with Snort2 are not vulnerable.

Affected Software

12 affected components
Cisco FirePOWER Management Center=3.1.0.1
Cisco Firepower Threat Defense>=6.4.0<6.4.0.13
Cisco Firepower Threat Defense>=6.6.0<6.6.5.1
Cisco Firepower Threat Defense>=6.7.0<6.7.0.3
Cisco Firepower Threat Defense>=7.0.0<7.0.1
Snort Snort>=3.0.0.0<3.1.0.100
Cisco Secure Firewall Management Center=3.1.0.1
Cisco Secure Firewall Threat Defense>=6.4.0<6.4.0.13
Cisco Secure Firewall Threat Defense>=6.6.0<6.6.5.1
Cisco Secure Firewall Threat Defense>=6.7.0<6.7.0.3
Cisco Secure Firewall Threat Defense>=7.0.0<7.0.1
Cisco Snort>=3.0.0.0<3.1.0.100

Event History

Oct 27, 2021
CVE Published
via MITRE·06:56 PM
Data Sourced
via MITRE·06:56 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·07:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is CVE-2021-40116?

CVE-2021-40116 is a vulnerability in Snort rules that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.

2

Which Cisco products are affected by CVE-2021-40116?

Cisco Firepower Management Center version 3.1.0.1, Cisco Firepower Threat Defense versions 6.4.0 to 6.4.0.13, 6.6.0 to 6.6.5.1, 6.7.0 to 6.7.0.3, and 7.0.0 to 7.0.1 are affected by CVE-2021-40116.

3

What is the severity of CVE-2021-40116?

CVE-2021-40116 has a severity score of 7.5 (high).

4

How can an attacker exploit CVE-2021-40116?

An attacker can exploit CVE-2021-40116 by sending specially crafted network traffic to the affected device.

5

Where can I find more information about CVE-2021-40116?

More information about CVE-2021-40116 can be found at the following link: [Cisco Security Advisory](https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-dos-RywH7ezM)

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