CVE-2018-0155
Cisco Catalyst Bidirectional Forwarding Detection Denial-of-Service Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 17 March 2022). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
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.
- CVSS 3.1
- 8.6 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
- EPSS
- 7.74% probability · 95th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Listed 3 March 2022 · due 17 March 2022
- Weakness
- CWE-388, CWE-755
- Affected
- cisco/ios · cisco/ios xe
- Source
- psirt@cisco.com
EPSS 7.7% since 27 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
CISA notes
Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2018-0155
References
- http://www.securityfocus.com/bid/103565Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1040587Third Party Advisory, VDB Entry
- https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05Third Party Advisory, US Government Resource
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-bfdVendor Advisory
- http://www.securityfocus.com/bid/103565Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1040587Third Party Advisory, VDB Entry
- https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05Third Party Advisory, US Government Resource
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-bfdVendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-0155US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.