8.6highHigh

CVE-2021-40116

Cisco Secure Firewall Management Center

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.

Exploitation status

  • A vendor advisory or patch reference has been published.

What the metrics mean

  • It is reachable over a network, without needing local access.
  • For an attacker who can reach it, no special conditions are needed to exploit it.
  • To exploit it, no account is needed.
  • Beyond that, no action by a user is required.

Scoring

CVSS
8.6 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Weakness
CWE-241
Assigned by
psirt@cisco.com

Dates

Published
2021-10-27
Last modified
2026-08-11
Sources
NVD

Affected products

  • Cisco Secure Firewall Management Center3.1.0.1
  • Cisco Secure Firewall Threat Defense6.4.0 - 6.4.0.13, 6.6.0 - 6.6.5.1, 6.7.0 - 6.7.0.3, 7.0.0 - 7.0.1
  • Cisco Snort3.0.0.0 - 3.1.0.100

As listed in the NVD configuration data. Not a statement about your estate.

References