Cisco Secure Firewall Threat Defense
CVE-2020-3255
A vulnerability in the packet processing functionality of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to inefficient memory management. An attacker could exploit this vulnerability by sending a high rate of IPv4 or IPv6 traffic through an affected device. This traffic would need to match a configured block action in an access control policy. An exploit could allow the attacker to cause a memory exhaustion condition on the affected device, which would result in a DoS for traffic transiting the device, as well as sluggish performance of the management interface. Once the flood is stopped, performance should return to previous states.
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
- 7.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/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
- Cisco Asa 5505 Firmware9.10\(1.3\)
- Cisco Asa 5505all versions
- Cisco Asa 5510 Firmware9.10\(1.3\)
- Cisco Asa 5510all versions
- Cisco Asa 5512-X Firmware9.10\(1.3\)
- Cisco Asa 5512-Xall versions
- Cisco Asa 5515-X Firmware9.10\(1.3\)
- Cisco Asa 5515-Xall versions
- Cisco Asa 5520 Firmware9.10\(1.3\)
- Cisco Asa 5520all versions
- Cisco Asa 5525-X Firmware9.10\(1.3\)
As listed in the NVD configuration data. Not a statement about your estate.