Findings

CVE-2018-0155

Cisco Catalyst Bidirectional Forwarding Detection Denial-of-Service Vulnerability

Published Mar 28, 2018 · updated Jun 16, 2026 · cisco ios

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.

Timeline

Detection, updates, and resolution for this record.

  1. Mar 28, 2018 · Catalog

    Detected

    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 incomp

  2. Mar 3, 2022 · CISA KEV

    Known exploited

    Apply updates per vendor instructions.

  3. Mar 17, 2022 · CISA KEV

    Remediation due

    Apply updates per vendor instructions.

  4. Jun 16, 2026 · Catalog

    Updated

    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 incomp

Required action

Apply updates per vendor instructions.

CISA due date Mar 17, 2022

Affected

  • cpe cisco/ios3.6\(2\)e
  • cpe cisco/ios xe3.6\(2\)e
  • vendor Cisco Catalyst 4500 Series Switches and Cisco Catalyst 4500-X Series Switchesversion unspecified

Sources

  • CISA KEVCVE-2018-0155

    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.

    cisa.gov
  • CVE.orgCVE-2018-0155

    Official CVE identifier

    cve.org
  • FIRST EPSSCVE-2018-0155

    30-day exploitation probability 7.7%

    first.org
  • NIST NVDCVE-2018-0155

    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 servic

    nvd.nist.gov

References