Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD)
CVE-2020-3580
Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) contain an insufficient input validation vulnerability for user-supplied input by the web services interface. Successful exploitation could allow an attacker to perform cross-site scripting (XSS) in the context of the interface or access sensitive browser-based information.
What this means for your business
- It affects Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD). It matters if your company, or a supplier that handles your data, runs it.
- Attackers are already using it. CISA added it to its list of flaws used in real attacks on 3 November 2021.
- Ransomware gangs are known to have used it.
- An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
- FIRST's prediction model gives it a 86% chance of attack attempts being seen in the next 30 days, ranking above 99% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD), 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.
- 3Treat it as urgent. US federal agencies must fix it by 3 May 2022. That deadline does not apply to private companies, but it shows how seriously CISA takes it.
- 4Because attackers have used it, check the affected systems for signs of a break-in, not only for the update.
Not sure if your company is exposed?
Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.
Required action
Apply updates per vendor instructions.
CISA’s wording, unedited.
Scoring
- CVSS
- 6.1 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N- Weakness
- CWE-79
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2021-11-03
- Last modified
- 2026-08-11
- Added to KEV
- 2021-11-03
- Remediation due
- 2022-05-03
- Sources
- CISA KEV, NVD
Affected products
- Cisco Secure Firewall Threat Defense- 6.4.0.12, 6.5.0 - 6.6.4, 6.7.0 - 6.7.0.2
- Cisco Adaptive Security Appliance Software- 9.8.4.34, 9.9 - 9.9.2.85, 9.10 - 9.12.4.13, 9.13 - 9.13.1.21, 9.14 - 9.14.2.8, 9.15 - 9.15.1.15
As listed in the NVD configuration data. Not a statement about your estate.