CVE-2025-20136
Published: Aug 14, 2025
Modified: Aug 14, 2025
CVSS v3.1
8.6
Description
A vulnerability in the function that performs IPv4 and IPv6 Network Address Translation (NAT) DNS inspection for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to an infinite loop condition that occurs when a Cisco Secure ASA or Cisco Secure FTD device processes DNS packets with DNS inspection enabled and the device is configured for NAT44, NAT64, or NAT46. An attacker could exploit this vulnerability by sending crafted DNS packets that match a static NAT rule with DNS inspection enabled through an affected device. A successful exploit could allow the attacker to create an infinite loop and cause the device to reload, resulting in a DoS condition.
| Vendor | Product | Versions |
|---|---|---|
Cisco | Cisco Adaptive Security Appliance (ASA) Software | affected 9.12.3affected 9.8.3affected 9.12.1affected 9.8.1affected 9.12.2+204 more versions |
Cisco | Cisco Firepower Threat Defense Software | affected 6.2.3.14affected 6.4.0.1affected 6.2.3.7affected 6.2.3affected 6.4.0.2+86 more versions |
Weaknesses (CWE)
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
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