CVE-2026-20084
published 2026-03-25CVE-2026-20084: 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…
PriorityP353high8.6CVSS 3.1
AVNACLPRNUINSCCNINAH
EPSS
0.35%
28.0th percentile
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.
Affected
108 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
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| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
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| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
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CVSS provenance
nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
vendor_cisco8.6HIGH
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Cisco
Cisco IOS XE Software for Catalyst 9000 Series Switches DHCP Snooping Denial of Service Vulnerability
vendor_cisco·2026-03-25·CVSS 8.6
CVE-2026-20084 [HIGH] CWE-400 Cisco IOS XE Software for Catalyst 9000 Series Switches DHCP Snooping Denial of Service Vulnerability
Cisco IOS XE Software for Catalyst 9000 Series Switches DHCP Snooping Denial of Service Vulnerability
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 t
Cisco
Cisco IOS XE Software for Catalyst 9000 Series Switches DHCP Snooping Denial of Service Vulnerability
vendor_cisco·CVSS 3.1
CVE-2026-20084 Cisco IOS XE Software for Catalyst 9000 Series Switches DHCP Snooping Denial of Service Vulnerability
CVE-2026-20084: Cisco IOS XE Software for Catalyst 9000 Series Switches DHCP Snooping Denial of Service Vulnerability
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
GHSA
GHSA-m8vf-g949-jwr2: A vulnerability in the DHCP snooping feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause BOOTP packets to be for
ghsa_unreviewed·2026-03-25
CVE-2026-20084 [HIGH] CWE-400 GHSA-m8vf-g949-jwr2: A vulnerability in the DHCP snooping feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause BOOTP packets to be for
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
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-03-25
Published