Cisco Adaptive Security Appliance
CVE-2020-3436
A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to upload arbitrary-sized files to specific folders on an affected device, which could lead to an unexpected device reload. The vulnerability exists because the affected software does not efficiently handle the writing of large files to specific folders on the local file system. An attacker could exploit this vulnerability by uploading files to those specific folders. A successful exploit could allow the attacker to write a file that triggers a watchdog timeout, which would cause the device to unexpectedly reload, causing a denial of service (DoS) condition.
What this means for your business
- It affects Cisco Adaptive Security Appliance. 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 78% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Cisco Adaptive Security Appliance, 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-434
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2020-10-21
- Last modified
- 2026-08-11
- Sources
- NVD
Affected products
- Cisco Adaptive Security Appliance- 9.6.4.45
- Cisco Secure Firewall Threat Defense- 6.2.2, 6.3.0 - 6.3.0.6, 6.4.0 - 6.4.0.10, 6.5.0 - 6.5.0.5, 6.6.0
- Cisco Adaptive Security Appliance Software9.8.0 - 9.8.4.25, 9.9.0 - 9.9.2.80, 9.10.0 - 9.10.1.44, 9.12.0 - 9.12.4.2, 9.13.0 - 9.13.1.12, 9.14.0 - 9.14.1.15
As listed in the NVD configuration data. Not a statement about your estate.