CISA KEV catalog
Confirmed active exploitation.
Listed in CISA's catalog of Known Exploited Vulnerabilities: attackers are using it in real attacks. Patch it with priority.
- Name
- Cisco Catalyst Bidirectional Forwarding Detection Denial-of-Service Vulnerability
- Added to catalog
- Remediation due date (US federal)
- Required action
- Apply updates per vendor instructions.
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.
Affected products
cisco: ios; cisco: ios xe; cisco: catalyst 4500-x series switches \(k10\); cisco: catalyst 4500 supervisor engine 6-e \(k5\); cisco: catalyst 4500 supervisor engine 6l-e \(k10\); cisco: catalyst 4500 supervisor engine 7-e \(k10\); cisco: catalyst 4500 supervisor engine 7l-e \(k10\); cisco: catalyst 4500e supervisor engine 8-e \(k10\); cisco: catalyst 4500e supervisor engine 8l-e \(k10\); cisco: catalyst 4500e supervisor engine 9-e \(k10\); cisco: catalyst 4900m switch \(k5\); cisco: catalyst 4948e ethernet switch \(k5\); rockwellautomation: allen-bradley stratix 8300 industrial managed ethernet switch
References9
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/c… Vendor Advisory
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/c… Vendor Advisory
- www.securityfocus.com/bid/103565 Third Party AdvisoryVDB Entry
- www.securitytracker.com/id/1040587 Third Party AdvisoryVDB Entry
- ics-cert.us-cert.gov/advisories/ICSA-18-107-05 Third Party AdvisoryUS Government Resource
- www.securityfocus.com/bid/103565 Third Party AdvisoryVDB Entry
- www.securitytracker.com/id/1040587 Third Party AdvisoryVDB Entry
- ics-cert.us-cert.gov/advisories/ICSA-18-107-05 Third Party AdvisoryUS Government Resource
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=… US Government Resource
Metrics
- CVSS 3.1
-
8.6
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H - EPSS — exploit probability
- 8% percentile: 95 · as of 10 November 2026
- CWE
- CWE-388CWE-755
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