CVE-2018-0155
Cisco Catalyst Bidirectional Forwarding Detection Denial-of-Service Vulnerability
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run Catalyst 4500 Series Switches and Cisco Catalyst 4500-X Series Switches, fix it now.
CISA required action: Apply updates per vendor instructions.
US federal civilian agencies must remediate by Mar 17, 2022.
Patch status
No official fix confirmed yet
Until a fix ships, follow the vendor's mitigations and CISA's required action, limit exposure of affected systems, and watch this record for a patch.
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.
Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.
Affected products
| Product | Vendor | Affected versions | Source |
|---|---|---|---|
| Catalyst 4500 Series Switches and Cisco Catalyst 4500-X Series Switches | Cisco | — | KEV |
| Cisco networking & security | Cisco | 3.6\(2\)e | NVD |
| IOS | Cisco | 3.6\(2\)e | NVD |
Sources: KEV = CISA Known Exploited Vulnerabilities catalog; NVD = NIST National Vulnerability Database.
Intelligence timeline
Developments from the last 30 days, newest first.
- CVSS scoredUpdateKEV
CVE-2018-0155 scored CVSS 8.6: Cisco Catalyst 4500 Series Switches and Cisco Catalyst 4500-X Series Switches, Cisco Catalyst Bidirectional Forwarding Detection Denial-of-Service Vulnerability
CISA lists this as exploited in the wild. Unpatched Catalyst 4500 Series Switches and Cisco Catalyst 4500-X Series Switches systems are exposed to active attacks now.
Basis: NIST National Vulnerability Database
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Coverage
We have not published a story about this vulnerability yet.