A vulnerability in the DHCP snooping feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause BOOTP packets to be forwarded between VLANs, resulting in a denial of service (DoS) condition.
This vulnerability is due to improper handling of BOOTP packets on Cisco Catalyst 9000 Series Switches. An attacker could exploit this vulnerability by sending BOOTP request packets to an affected device. A successful exploit could allow an attacker to forward BOOTP packets from one VLAN to another, resulting in BOOTP VLAN leakage and potentially leading to high CPU utilization. This makes the device unreachable (either through console or remote management) and unable to forward traffic, resulting in a DoS condition.
Note: This vulnerability can be exploited with either unicast or broadcast BOOTP packets.
There are workarounds that address this vulnerability.
References
Configurations
No configuration.
History
No history.
Information
Published : 2026-03-25 16:16
Updated : 2026-03-26 15:13
NVD link : CVE-2026-20084
Mitre link : CVE-2026-20084
CVE.ORG link : CVE-2026-20084
JSON object : View
Products Affected
No product.
CWE
CWE-400
Uncontrolled Resource Consumption
