Cisco Secure Firewall Threat Defense
CVE-2021-40125
A vulnerability in the Internet Key Exchange Version 2 (IKEv2) implementation of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to trigger a denial of service (DoS) condition on an affected device. This vulnerability is due to improper control of a resource. An attacker with the ability to spoof a trusted IKEv2 site-to-site VPN peer and in possession of valid IKEv2 credentials for that peer could exploit this vulnerability by sending malformed, authenticated IKEv2 messages to an affected device. A successful exploit could allow the attacker to trigger a reload of the device.
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, with an ordinary user login, and without anyone at your company clicking anything.
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
- 5.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H- Weakness
- CWE-416
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2021-10-27
- Last modified
- 2026-08-11
- Sources
- NVD
Affected products
- Cisco Secure Firewall Threat Defense- 6.4.0.13, 6.6.0 - 6.6.5, 6.7.0 - 6.7.0.3, 7.0.0 - 7.0.1
- Cisco Adaptive Security Appliance Software9.8.0 - 9.8.4.40, 9.9.0 - 9.12.4.30, 9.14.0 - 9.14.3.9, 9.15.0 - 9.15.1.17, 9.16.0 - 9.16.2
- Cisco Asa 5512-X Firmware009.016\(001.025\)
- Cisco Asa 5512-Xall versions
- Cisco Asa 5505 Firmware009.016\(001.025\)
- Cisco Asa 5505all versions
- Cisco Asa 5515-X Firmware009.016\(001.025\)
- Cisco Asa 5515-Xall versions
- Cisco Asa 5525-X Firmware009.016\(001.025\)
- Cisco Asa 5525-Xall versions
- Cisco Asa 5545-X Firmware009.016\(001.025\)
- Cisco Asa 5545-Xall versions
As listed in the NVD configuration data. Not a statement about your estate.