CVE-2021-40125: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software IKEv2 Site-to-Site VPN Denial of Service Vulnerability

Published Oct 27, 2021
·
Updated

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.

Affected Software

25 affected components
Cisco Firepower Threat Defense<6.4.0.13
Cisco Firepower Threat Defense>=6.6.0<6.6.5
Cisco Firepower Threat Defense>=6.7.0<6.7.0.3
Cisco Firepower Threat Defense>=7.0.0<7.0.1
Cisco Adaptive Security Appliance Software>=9.8.0<9.8.4.40
Cisco Adaptive Security Appliance Software>=9.9.0<9.12.4.30
Cisco Adaptive Security Appliance Software>=9.14.0<9.14.3.9
Cisco Adaptive Security Appliance Software>=9.15.0<9.15.1.17
Cisco Adaptive Security Appliance Software>=9.16.0<9.16.2
Cisco Asa 5512-x Firmware=009.016\(001.025\)
Cisco Asa 5512-x
Cisco Asa 5505 Firmware=009.016\(001.025\)
Cisco Asa 5505
Cisco Asa 5515-x Firmware=009.016\(001.025\)
Cisco Asa 5515-x
Cisco Asa 5525-x Firmware=009.016\(001.025\)
Cisco Asa 5525-x
Cisco Asa 5545-x Firmware=009.016\(001.025\)
Cisco Asa 5545-x
Cisco Asa 5555-x Firmware=009.016\(001.025\)
Cisco Asa 5555-x
Cisco Asa 5580 Firmware=009.016\(001.025\)
Cisco Asa 5580
Cisco Asa 5585-x Firmware=009.016\(001.025\)
Cisco Asa 5585-x

Event History

Oct 27, 2021
CVE Published
via MITRE·06:50 PM
Data Sourced
via MITRE·06:50 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2021-40125?

CVE-2021-40125 is 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 that could allow an authenticated, remote attacker to trigger a denial of service (DoS) condition on an affected device.

2

Which software products are affected by CVE-2021-40125?

Cisco Adaptive Security Appliance (ASA) Software versions 9.8.0 to 9.8.4.40, 9.9.0 to 9.12.4.30, 9.14.0 to 9.14.3.9, 9.15.0 to 9.15.1.17, and 9.16.0 to 9.16.2, as well as Cisco Firepower Threat Defense (FTD) Software versions 6.4.0.13, 6.6.0 to 6.6.5, 6.7.0 to 6.7.0.3, and 7.0.0 to 7.0.1 are affected.

3

What is the severity of CVE-2021-40125?

The severity of CVE-2021-40125 is medium, with a severity value of 6.5.

4

How can I fix the vulnerability CVE-2021-40125?

To fix the vulnerability CVE-2021-40125, it is recommended to upgrade to a fixed software version as indicated in the Cisco Security Advisory.

5

Where can I find more information about CVE-2021-40125?

You can find more information about CVE-2021-40125 in the Cisco Security Advisory at the following link: [https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ikev2-dos-g4cmrr7C](https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ikev2-dos-g4cmrr7C)

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