#VU11362 Improper input validation in Cisco IOS XE - CVE-2018-0173
Published: March 30, 2018 / Updated: March 8, 2022
Vulnerability identifier: #VU11362
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:A/U:Green
CVE-ID: CVE-2018-0173
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
The vulnerability is being exploited in the wild
Vulnerable software:
Cisco IOS XE
Cisco IOS XE
Software vendor:
Cisco Systems, Inc
Cisco Systems, Inc
Description
The vulnerability allows a remote unauthenticated attacker to cause DoS condition on the target system.
The weakness exists in the function that restores encapsulated option 82 information in DHCP Version 4 (DHCPv4) packets due to incomplete input validation of encapsulated option 82 information that it receives in DHCPOFFER messages from DHCPv4 servers. A remote attacker can send a specially crafted DHCPv4 packet and cause the service to crash.
The weakness exists in the function that restores encapsulated option 82 information in DHCP Version 4 (DHCPv4) packets due to incomplete input validation of encapsulated option 82 information that it receives in DHCPOFFER messages from DHCPv4 servers. A remote attacker can send a specially crafted DHCPv4 packet and cause the service to crash.
Remediation
Update to evrsions 16.6(2.67), 16.5(1.321), 16.3(5.73), 15.6(2.18)SP3, 15.6(2)SP4, 15.5(3)S6.23, 15.4(3)S9, 15.2(6.5.1i)E1, 15.2(6.4.66i)E1, 15.2(6.4.63i)E1, 15.2(6)E1, 15.2(4.7.6)EA7, 15.0(1.9.1)SQD8 or 12.2(60)EZ13.