Cisco Secure Firewall Threat Defense
CVE-2020-3283
A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) handler of Cisco Firepower Threat Defense (FTD) Software when running on the Cisco Firepower 1000 Series platform could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to a communication error between internal functions. An attacker could exploit this vulnerability by sending a crafted SSL/TLS message to an affected device. A successful exploit could allow the attacker to cause a buffer underrun, which leads to a crash. The crash causes the affected device to reload.
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 79% 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-119
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2020-05-06
- Last modified
- 2026-08-11
- Sources
- NVD
Affected products
- Cisco Secure Firewall Threat Defense6.4.0 - 6.4.0.9
- Cisco Firepower 1010all versions
- Cisco Firepower 1020all versions
- Cisco Firepower 1030all versions
- Cisco Firepower 1040all versions
- Cisco Asa 5505 Firmware9.12\(2.12\), 9.13\(0.33\)
- Cisco Asa 5505all versions
- Cisco Asa 5510 Firmware9.12\(2.12\), 9.13\(0.33\)
- Cisco Asa 5510all versions
- Cisco Asa 5512-X Firmware9.12\(2.12\), 9.13\(0.33\)
- Cisco Asa 5512-Xall versions
- Cisco Asa 5515-X Firmware9.12\(2.12\), 9.13\(0.33\)
As listed in the NVD configuration data. Not a statement about your estate.