CVE-2018-0155

Cisco Catalyst Bidirectional Forwarding Detection Denial-of-Service

8.6 HIGHActively exploited (CISA KEV)EPSS 7.74%

Published28 Mar 2018
Added to CISA KEV3 Mar 2022
Remediation due17 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.

CVSS 3.1 breakdown

Attack vectorNetwork

Attack complexityLow

Privileges requiredNone

User interactionNone

ScopeChanged

ConfidentialityNone

IntegrityNone

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Affected products

Cisco iOS3.6\(2\)e

Cisco iOS XE3.6\(2\)e

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

Patch & vendor advisories

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-bfd

References

https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05Third Party AdvisoryUS 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
http://www.securityfocus.com/bid/103565Third Party AdvisoryVDB Entry
http://www.securitytracker.com/id/1040587Third Party AdvisoryVDB Entry

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2018-0155 being actively exploited?

Yes. CVE-2018-0155 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 3 Mar 2022.

How severe is CVE-2018-0155?

CVE-2018-0155 has a CVSS 3.1 base score of 8.6, rated high. EPSS estimates a 7.74% probability of exploitation.

Which products are affected by CVE-2018-0155?

Affected products include Cisco iOS, Cisco iOS XE.

How do I fix CVE-2018-0155?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2018-0155 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, Secuno flags any affected asset as top-priority automatically. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.