Cisco Secure Firewall Threat Defense
CVE-2021-1504
Multiple vulnerabilities in Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. These vulnerabilities are due to lack of proper input validation of the HTTPS request. An attacker could exploit these vulnerabilities by sending a crafted HTTPS request to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: This vulnerability affects only specific AnyConnect and WebVPN configurations. For more information, see the Vulnerable Products section.
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 75% 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-787
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2021-04-29
- Last modified
- 2026-08-11
- Sources
- NVD
Affected products
- Cisco Secure Firewall Threat Defense6.5.0 - 6.6.4, 6.7.0 - 6.7.0.1
- Cisco Adaptive Security Appliance Software9.7 - 9.8.4.35, 9.9 - 9.9.2.85, 9.10 - 9.12.4.10, 9.13 - 9.13.1.21, 9.14 - 9.14.2.4, 9.15 - 9.15.1.7
As listed in the NVD configuration data. Not a statement about your estate.