CVE EVIDENCE REVIEW
ReviewHighEvidence review

CVE-2021-40116 evidence review

Cisco Cisco Firepower Threat Defense Software, secure firewall management center, secure firewall threat defense

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 ru...

Open CVE record
Evidence review

This record remains available for product and version identification, but it is not presented as a complete remediation procedure. Confirm the affected range and the supported fix in a direct vendor advisory before changing production systems.

ProductCisco Cisco Firepower Threat Defense Software, secure firewall management center, secure firewall threat defense
Affected versions3.1.0.1, >= 6.4.0 < 6.4.0.13, >= 6.6.0 < 6.6.5.1, >= 6.7.0 < 6.7.0.3, >= 7.0.0 < 7.0.1, >= 3.0.0.0 < 3.1.0.100
Fixed versions6.4.0.13, 6.6.5.1, 6.7.0.3, 7.0.1, 3.1.0.100
Priority basisReview · CVSS 7.5 · EPSS 1.39%
01

Identify the product and installed version

Record whether Cisco Cisco Firepower Threat Defense Software, secure firewall management center, secure firewall threat defense is present, where it is installed, and which interfaces are exposed.

  • Record the product name, package or appliance identifier, and installed version.
  • Identify internet-facing, administrative, API, and internal access paths.
  • Preserve the pre-change configuration and relevant service logs.
02

Compare the affected range

Use the current record as an identification aid: 3.1.0.1, >= 6.4.0 < 6.4.0.13, >= 6.6.0 < 6.6.5.1, >= 6.7.0 < 6.7.0.3, >= 7.0.0 < 7.0.1, >= 3.0.0.0 < 3.1.0.100. Resolve incomplete inventory results before deciding that an asset is unaffected.

03

Verify the authoritative remediation source

Open the linked source material and locate a direct vendor advisory for this CVE. Confirm the supported fixed release and product-specific update path before making a production change.

Operational boundary

This page does not replace the vendor advisory, support contract, change-management process, or recovery plan. Do not infer that an asset is unaffected from an incomplete inventory query or a missing fixed-version field.