What’s Vulnerable › Vulnerabilities

CVE-2019-1751: Cisco IOS Software NAT64 Denial of Service Vulnerability

• Severity: high (CVSS 7.5 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2019-03-28 · updated 2026-06-17
• Weakness: CWE-20

Description

A vulnerability in the Network Address Translation 64 (NAT64) functions of Cisco IOS Software could allow an unauthenticated, remote attacker to cause either an interface queue wedge or a device reload. The vulnerability is due to the incorrect handling of certain IPv4 packet streams that are sent through the device. An attacker could exploit this vulnerability by sending specific IPv4 packet streams through the device. An exploit could allow the attacker to either cause an interface queue wedge or a device reload, resulting in a denial of service (DoS) condition.

Affected products

• Cisco IOS: 15.4(1)cg1, 15.4(1)t, 15.4(1)t1, 15.4(1)t2, 15.4(1)t3, 15.4(1)t4 (+74)

References

• http://www.securityfocus.com/bid/107601
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190327-nat64
• http://www.securityfocus.com/bid/107601
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190327-nat64

Get alerted when CVE-2019-1751 or the next vulnerability affects your stack