CVE-2019-12657

A vulnerability in Unified Threat Defense (UTD) in Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to improper validation of IPv6 packets through the UTD feature. An attacker could exploit this vulnerability by sending IPv6 traffic through an affected device that is configured with UTD. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition.

• CWE-20
• CWE-20

• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-utdVendor Advisory
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190925-utdVendor Advisory

Published

Sep 25, 2019

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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