A vulnerability in the DNS over TCP implementation of 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 TCP DNS response handler to unexpectedly restart, causing the device to reload.
This vulnerability is due to a logic error when parsing a DNS query and tracking the size of the incoming buffers. An attacker could exploit this vulnerability by formatting a crafted reply to a DNS query sent from the targeted device. A successful exploit could allow the attacker to cause the device to reload, causing a denial of service (DoS) condition.
Note: The attacker must be able to respond to DNS queries from the device, either by controlling the DNS service or through a machine-in-the-middle attack.
References
Configurations
No configuration.
History
16 Sep 2026, 21:17
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-09-16 21:17
Updated : 2026-09-18 13:28
NVD link : CVE-2026-20248
Mitre link : CVE-2026-20248
CVE.ORG link : CVE-2026-20248
JSON object : View
Products Affected
No product.
CWE
CWE-195
Signed to Unsigned Conversion Error