Cisco Secure Firewall Threat Defense
CVE-2020-3189
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.
What this means for your business
- It affects Cisco Secure Firewall Threat Defense. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 2% chance of attack attempts being seen in the next 30 days, ranking above 77% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Cisco Secure Firewall Threat Defense, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Not sure if your company is exposed?
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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-400
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2020-05-06
- Last modified
- 2026-08-11
- Sources
- NVD
Affected products
- Cisco Secure Firewall Threat Defense6.2.3.12, 6.2.3.13, 6.2.3.14, 6.2.3.15
- Cisco Asa 5505 Firmware9.9\(2\), 9.9\(2.21\), 9.9\(2.52\), 9.9\(2.55\)
- Cisco Asa 5505all versions
- Cisco Asa 5510 Firmware9.9\(2\), 9.9\(2.21\), 9.9\(2.52\), 9.9\(2.55\)
- Cisco Asa 5510all versions
- Cisco Asa 5512-X Firmware9.9\(2\), 9.9\(2.21\), 9.9\(2.52\), 9.9\(2.55\)
- Cisco Asa 5512-Xall versions
- Cisco Asa 5515-X Firmware9.9\(2\), 9.9\(2.21\), 9.9\(2.52\), 9.9\(2.55\)
- Cisco Asa 5515-Xall versions
- Cisco Asa 5520 Firmware9.9\(2\), 9.9\(2.21\), 9.9\(2.52\), 9.9\(2.55\)
- Cisco Asa 5520all versions
- Cisco Asa 5525-X Firmware9.9\(2\), 9.9\(2.21\), 9.9\(2.52\), 9.9\(2.55\)
As listed in the NVD configuration data. Not a statement about your estate.