Cisco Adaptive Security Appliance
CVE-2020-3561
A vulnerability in the Clientless SSL VPN (WebVPN) of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to inject arbitrary HTTP headers in the responses of the affected system. The vulnerability is due to improper input sanitization. An attacker could exploit this vulnerability by persuading a user of the interface to click a crafted link. A successful exploit could allow the attacker to conduct a CRLF injection attack, adding arbitrary HTTP headers in the responses of the system and redirecting the user to arbitrary websites.
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, but only after tricking someone into an action such as opening a file or a link.
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
- 4.7 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N- Weakness
- CWE-93
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2020-10-21
- Last modified
- 2026-08-11
- Sources
- NVD
Affected products
- Cisco Adaptive Security Appliance- 9.6.4.35
- Cisco Secure Firewall Threat Defense- 6.3.0.6, 6.4.0 - 6.4.0.10, 6.5.0 - 6.5.0.5, 6.6.0 - 6.6.1
- Cisco Adaptive Security Appliance Software9.8.0 - 9.8.4.20, 9.9.0 - 9.9.2.80, 9.10.0 - 9.10.1.43, 9.12.0 - 9.12.3.9, 9.13.0 - 9.13.1.10, 9.14.0 - 9.14.1.10
As listed in the NVD configuration data. Not a statement about your estate.