CVE-2018-0155
Cisco Catalyst Bidirectional Forwarding Detection Denial-of-Service Vulnerability
- High 8.6
- Exploited: added to CISA KEV 3 Mar 2022
Description
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.
Key facts
- Published
- 28 Mar 2018
- Last changed
- 12 Jan 2026
- Assigned by
- cisco
- KEV added
- 3 Mar 2022
- KEV fix due
- 17 Mar 2022
- EPSS
- 7.742% likely to be exploited in the next 30 days, higher than 94.721% of CVEs (scores for 15 Nov 2026)
- SSVC (CISA)
- Exploitation: active; Automatable: yes; Technical impact: partial
Severity scores
Each score is shown as its source gave it. They are not averaged or merged.
- 8.6CVSS 3.1, Highfrom CISA (ADP container)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
What to do
- Apply updates per vendor instructions.CISA KEV required action
Historical context and remediation
This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.
No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.
Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.
Affected products
| Vendor | Product | Versions |
|---|---|---|
| n/a | Cisco IOS and IOS XE |
|
Timeline
- 28 Mar 2018 Published
- 3 Mar 2022 Added to the CISA KEV catalogue