high8.6Known exploited

CVE-2018-0173

Cisco IOS and IOS XE Software Improper Input Validation Vulnerability

Exploited in the wild

This vulnerability is on a Known Exploited Vulnerabilities catalogue, added 2022-03-03. Federal due date: 2022-03-17.

Apply updates per vendor instructions.

Impact

A vulnerability in the Cisco IOS Software and Cisco IOS XE Software function that restores encapsulated option 82 information in DHCP Version 4 (DHCPv4) packets could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a Relay Reply denial of service (DoS) condition. The vulnerability exists because the affected software performs incomplete input validation of encapsulated option 82 information that it receives in DHCPOFFER messages from DHCPv4 servers. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device, which the device would then forward to a DHCPv4 server. When the affected software processes the option 82 information that is encapsulated in the response from the server, an error could occur. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCvg62754.

Affected products

Vendor	Product	Affected versions
Cisco	Ios	through 15.2\(6\)e0a through 15.2\(4a\)ea5 Version denali-16.3.4
Cisco	Ios Xe	through 15.2\(6\)e0a through 15.2\(4a\)ea5 Version denali-16.3.4

Weakness classification

CWE-20

Exploited in the wild

Impact

Affected products

Weakness classification

References