Medium severity · published Oct 27, 2021
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…
6.5
CVSS
1%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 63% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
Adaptive Security Appliance Software · Cisco
9.8.0 before 9.8.4.40; 9.9.0 before 9.12.4.30; 9.14.0 before 9.14.3.9; 9.15.0 before 9.15.1.17; 9.16.0 before 9.16.2 · source: NVD
A5
Asa 5505 Firmware · Cisco
009.016(001.025) · source: NVD
A5
Asa 5512-x Firmware · Cisco
009.016(001.025) · source: NVD
A5
Asa 5515-x Firmware · Cisco
009.016(001.025) · source: NVD
A5
Asa 5525-x Firmware · Cisco
009.016(001.025) · source: NVD
A5
Asa 5545-x Firmware · Cisco
009.016(001.025) · source: NVD
A5
Asa 5555-x Firmware · Cisco
009.016(001.025) · source: NVD
A5
Asa 5580 Firmware · Cisco
009.016(001.025) · source: NVD
A5
Asa 5585-x Firmware · Cisco
009.016(001.025) · source: NVD
SF
Secure Firewall Threat Defense · Cisco
before 6.4.0.13; 6.6.0 before 6.6.5; 6.7.0 before 6.7.0.3; 7.0.0 before 7.0.1 · source: NVD
Affected product
AS
Adaptive Security Appliance Software
Cisco
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-40125
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-40125
Vendor Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ikev2-dos-g4cmrr7C
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