CVE-2026-20084High· 8.6▾ TwilightA 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 vulner…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 47.3 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Sep 28.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.4%
0.4% → 0.4%
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.
ios_xe = 16.6.1ios_xe = 16.6.2ios_xe = 16.6.3ios_xe = 16.6.4ios_xe = 16.6.4aios_xe = 16.6.5ios_xe = 16.6.6ios_xe = 16.6.7ios_xe = 16.6.8ios_xe = 16.6.9ios_xe = 16.6.10ios_xe = 16.7.1ios_xe = 16.8.1ios_xe = 16.8.1aios_xe = 16.8.1sios_xe = 16.9.1ios_xe = 16.9.1sios_xe = 16.9.2ios_xe = 16.9.3ios_xe = 16.9.4ios_xe = 16.9.5ios_xe = 16.9.6ios_xe = 16.9.7ios_xe = 16.9.8ios_xe = 16.10.1ios_xe = 16.10.1eios_xe = 16.10.1sios_xe = 16.11.1ios_xe = 16.11.1bios_xe = 16.11.1sios_xe = 16.12.1ios_xe = 16.12.1cios_xe = 16.12.1sios_xe = 16.12.2ios_xe = 16.12.2sios_xe = 16.12.3ios_xe = 16.12.3aios_xe = 16.12.3sios_xe = 16.12.4ios_xe = 16.12.4aios_xe = 16.12.5ios_xe = 16.12.5bios_xe = 16.12.6ios_xe = 16.12.6aios_xe = 16.12.7ios_xe = 16.12.8ios_xe = 17.1.1ios_xe = 17.1.1sios_xe = 17.1.1tios_xe = 17.1.3ios_xe = 17.2.1ios_xe = 17.2.1aios_xe = 17.3.1ios_xe = 17.3.2ios_xe = 17.3.2aios_xe = 17.3.3ios_xe = 17.3.4ios_xe = 17.3.5ios_xe = 17.3.6ios_xe = 17.3.7ios_xe = 17.3.8ios_xe = 17.3.8aios_xe = 17.4.1ios_xe = 17.5.1ios_xe = 17.6.1ios_xe = 17.6.1yios_xe = 17.6.2ios_xe = 17.6.3ios_xe = 17.6.4ios_xe = 17.6.5ios_xe = 17.6.5aios_xe = 17.6.6ios_xe = 17.6.6aios_xe = 17.6.7ios_xe = 17.6.8ios_xe = 17.7.1ios_xe = 17.8.1ios_xe = 17.9.1ios_xe = 17.9.2ios_xe = 17.9.3ios_xe = 17.9.4ios_xe = 17.9.4aios_xe = 17.9.5ios_xe = 17.9.6ios_xe = 17.9.6aios_xe = 17.9.7ios_xe = 17.9.8ios_xe = 17.10.1ios_xe = 17.10.1bios_xe = 17.11.1ios_xe = 17.12.1ios_xe = 17.12.1z5ios_xe = 17.12.2ios_xe = 17.12.3ios_xe = 17.12.4ios_xe = 17.12.5ios_xe = 17.13.1ios_xe = 17.14.1ios_xe = 17.15.1ios_xe = 17.15.2Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Connected by shared product, vendor, weakness, or advisory.
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