Cisco Secure Firewall Threat Defense
CVE-2020-3196
A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) handler of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to exhaust memory resources on the affected device, leading to a denial of service (DoS) condition. The vulnerability is due to improper resource management for inbound SSL/TLS connections. An attacker could exploit this vulnerability by establishing multiple SSL/TLS connections with specific conditions to the affected device. A successful exploit could allow the attacker to exhaust the memory on the affected device, causing the device to stop accepting new SSL/TLS connections and resulting in a DoS condition for services on the device that process SSL/TLS traffic. Manual intervention is required to recover an affected device.
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 80% 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 - 6.2.3.16, 6.3.0 - 6.3.0.6, 6.4.0 - 6.4.0.9, 6.5.0 - 6.5.0.5
- Cisco Asa 5505 Firmware9.4\(4\), 9.8\(4.18\), 100.13\(0\)
- Cisco Asa 5505all versions
- Cisco Asa 5510 Firmware9.4\(4\), 9.8\(4.18\), 100.13\(0\)
- Cisco Asa 5510all versions
- Cisco Asa 5512-X Firmware9.4\(4\), 9.8\(4.18\), 100.13\(0\)
- Cisco Asa 5512-Xall versions
- Cisco Asa 5515-X Firmware9.4\(4\), 9.8\(4.18\), 100.13\(0\)
- Cisco Asa 5515-Xall versions
- Cisco Asa 5520 Firmware9.4\(4\), 9.8\(4.18\), 100.13\(0\)
- Cisco Asa 5520all versions
- Cisco Asa 5525-X Firmware9.4\(4\), 9.8\(4.18\), 100.13\(0\)
As listed in the NVD configuration data. Not a statement about your estate.