Vulnerability in Cisco Firepower Threat Defense Software

CVE-2021-40116

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.014 (71.9th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 72nd percentile — 71.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-40116: held from 0.014 to 0.014.

EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-40116?
CVE-2021-40116 is a high-severity vulnerability in Cisco Firepower Threat Defense Software, classified under CWE-241. CVSS score: 8.6/10. Published 2021-10-27.
How severe is CVE-2021-40116?
High severity. CVSS v3 base score is 8.6 out of 10.