Firepower Threat Defense
CVE-2020-3189
HIGH
Severity by source
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Lifecycle Timeline
1DescriptionNVD
A vulnerability in the VPN System Logging functionality for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a memory leak that can deplete system memory over time, which can cause unexpected system behaviors or device crashes. The vulnerability is due to the system memory not being properly freed for a VPN System Logging event generated when a VPN session is created or deleted. An attacker could exploit this vulnerability by repeatedly creating or deleting a VPN tunnel connection, which could leak a small amount of system memory for each logging event. A successful exploit could allow the attacker to cause system memory depletion, which can lead to a systemwide denial of service (DoS) condition. The attacker does not have any control of whether VPN System Logging is configured or not on the device, but it is enabled by default.
AnalysisAI
A vulnerability in the VPN System Logging functionality for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a memory leak that can deplete. Rated high severity (CVSS 8.6), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified as Uncontrolled Resource Consumption (CWE-400), which allows attackers to cause denial of service by exhausting system resources. A vulnerability in the VPN System Logging functionality for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a memory leak that can deplete system memory over time, which can cause unexpected system behaviors or device crashes. The vulnerability is due to the system memory not being properly freed for a VPN System Logging event generated when a VPN session is created or deleted. An attacker could exploit this vulnerability by repeatedly creating or deleting a VPN tunnel connection, which could leak a small amount of system memory for each logging event. A successful exploit could allow the attacker to cause system memory depletion, which can lead to a systemwide denial of service (DoS) condition. The attacker does not have any control of whether VPN System Logging is configured or not on the device, but it is enabled by default. Affected products include: Cisco Firepower Threat Defense, Cisco Asa 5505 Firmware, Cisco Asa 5510 Firmware, Cisco Asa 5512-X Firmware, Cisco Asa 5515-X Firmware.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Implement rate limiting, set resource quotas, validate input sizes, use timeouts.
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Same weakness CWE-400 – Uncontrolled Resource Consumption
View allSame technique Denial Of Service
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External POC / Exploit Code
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