CVE-2021-40116

Multiple Cisco Products Snort Rule Denial of Service Vulnerability

Description

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.

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.78% Top 30%
Vendor Advisory cisco.com
Affected: Cisco Cisco Firepower Threat Defense Software
Published at:
Updated at:

References

Link Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-dos-RywH7ezM vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-40116?
CVE-2021-40116 has been scored as a high severity vulnerability.
How to fix CVE-2021-40116?
To fix CVE-2021-40116, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-40116 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-40116 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-40116?
CVE-2021-40116 affects Cisco Cisco Firepower Threat Defense Software.
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