Firepower Threat Defense
CVE-2024-20407
MEDIUM
Severity by source
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Primary rating from Vendor (cisco) · only source for this CVE.
CVSS VectorVendor: cisco
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Lifecycle Timeline
1DescriptionCVE.org
A vulnerability in the interaction between the TCP Intercept feature and the Snort 3 detection engine on Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured policies on an affected system. Devices that are configured with Snort 2 are not affected by this vulnerability. This vulnerability is due to a logic error when handling embryonic (half-open) TCP connections. An attacker could exploit this vulnerability by sending a crafted traffic pattern through an affected device. A successful exploit could allow unintended traffic to enter the network protected by the affected device.
AnalysisAI
A vulnerability in the interaction between the TCP Intercept feature and the Snort 3 detection engine on Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker. Rated medium severity (CVSS 5.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified under CWE-399. A vulnerability in the interaction between the TCP Intercept feature and the Snort 3 detection engine on Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured policies on an affected system. Devices that are configured with Snort 2 are not affected by this vulnerability. This vulnerability is due to a logic error when handling embryonic (half-open) TCP connections. An attacker could exploit this vulnerability by sending a crafted traffic pattern through an affected device. A successful exploit could allow unintended traffic to enter the network protected by the affected device. Affected products include: Cisco Firepower Threat Defense.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
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Same weakness CWE-399 – Resource Management Errors
View allSame technique Authentication Bypass
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External POC / Exploit Code
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