Live › vulnerability › CVE-2018-0172
Go to dashboardA flaw in how Cisco IOS and IOS XE handle DHCP option 82 encapsulation lets a crafted input crash the device, causing denial of service. CISA lists it as exploited in the wild.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 19:11 UTC, 3h before NVD. All times on this page are UTC.
Apply updates per vendor instructions.
| Product | Ecosystem | Affected | Fixed in |
|---|---|---|---|
| Cisco IOS and IOS XE Software | vendor | – | – |
Run show version on each Cisco IOS or IOS XE device and compare against the fixed release in the Cisco advisory; check whether DHCP relay or option 82 handling is configured.
Apply the update from Ciscos security advisory for the affected IOS or IOS XE train, per CISAs required action.
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
A vulnerability in the DHCP option 82 encapsulation functionality of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability exists because the affected software performs incomplete input validation of option 82 information that it receives in DHCP Version 4 (DHCPv4) packets from DHCP relay agents. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device. A successful exploit could allow the attacker to cause a heap overflow condition on the affected device, which will cause the device to reload and result in a DoS condition. Cisco Bug IDs: CSCvg62730.
This page as .md · .json · in your agent: get_signal("CVE-2018-0172")
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