CVE-2025-20311High· 7.4▾ TwilightA vulnerability in the handling of certain Ethernet frames in Cisco IOS XE Software for Catalyst 9000 Series Switches could allow an unauthenticated, adjacent attacker to cause an egress port to become blocked and drop all outbound traff…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 40.7 · likelihood 0 · exploitation 0
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Exploit-prediction probability, daily snapshots since Sep 17.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.2%
Last analysed / modified upstream
A vulnerability in the handling of certain Ethernet frames in Cisco IOS XE Software for Catalyst 9000 Series Switches could allow an unauthenticated, adjacent attacker to cause an egress port to become blocked and drop all outbound traffic.
This vulnerability is due to improper handling of crafted Ethernet frames. An attacker could exploit this vulnerability by sending crafted Ethernet frames through an affected switch. A successful exploit could allow the attacker to cause the egress port to which the crafted frame is forwarded to start dropping all frames, resulting in a denial of service (DoS) condition.
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 = 16.12.14ios_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 = 17.3.4bios_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 = 17.10.1ios_xe = 17.10.1bios_xe = 17.11.1ios_xe = 17.11.99swios_xe = 17.12.1ios_xe = 17.12.1z3ios_xe = 17.12.2ios_xe = 17.12.3ios_xe = 17.12.4ios_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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