from disclosure to weapon
Action required by CISAfederal deadline: 2022-03-17
Apply updates per vendor instructions.
In short
A flaw in Cisco Catalyst 4500 switches allows an attacker to crash the system by sending a malformed network message, causing it to restart and disrupt network service. No authentication is required to exploit this vulnerability.
Technical detail
The vulnerability exists in BFD (Bidirectional Forwarding Detection) offload processing due to insufficient validation of incomplete BFD packet headers. An unauthenticated remote attacker can send a crafted BFD message to trigger improper error handling in the iosd process, resulting in a denial of service via system reload.
Summary generated and translated by AI from the official description.
The full analysis of this CVE is available in Portuguese →
A vulnerability in the Bidirectional Forwarding Detection (BFD) offload implementation of Cisco Catalyst 4500 Series Switches and Cisco Catalyst 4500-X Series Switches could allow an unauthenticated, remote attacker to cause a crash of the iosd process, causing a denial of service (DoS) condition. The vulnerability is due to insufficient error handling when the BFD header in a BFD packet is incomplete. An attacker could exploit this vulnerability by sending a crafted BFD message to or across an affected switch. A successful exploit could allow the attacker to trigger a reload of the system. This vulnerability affects Catalyst 4500 Supervisor Engine 6-E (K5), Catalyst 4500 Supervisor Engine 6L-E (K10), Catalyst 4500 Supervisor Engine 7-E (K10), Catalyst 4500 Supervisor Engine 7L-E (K10), Catalyst 4500E Supervisor Engine 8-E (K10), Catalyst 4500E Supervisor Engine 8L-E (K10), Catalyst 4500E Supervisor Engine 9-E (K10), Catalyst 4500-X Series Switches (K10), Catalyst 4900M Switch (K5), Catalyst 4948E Ethernet Switch (K5). Cisco Bug IDs: CSCvc40729.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H