VulnTideExploited vulnerabilities, by vendor. Data as of 28 Oct 2026.
Known exploitedIn CISA's KEV catalog since 3 March 2022Ransomware use: unknown
Cisco Catalyst 4500 Series Switches and Cisco Catalyst 4500-X Series Switches

CVE-2018-0155: Cisco Catalyst Bidirectional Forwarding Detection Denial-of-Service Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 3 Mar 2022, 1,436 days after the CVE record was published.

How likely is exploitation in the next 30 days?
7.7%

EPSS score, percentile 94.6 of all scored records

How severe?
8.6 High

CVSS v3.1 base score, from CISA's enrichment of the record

What should I do?

CISA deadline 17 Mar 2022. Apply updates per vendor instructions.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

  • Cisco IOS and IOS XE

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

Required action, set by CISA

Apply updates per vendor instructions.

CISA due date for this action: 17 March 2022.

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

Linked from CISA's catalog entry

Affected products and versions

As listed in the CVE record.

n/a Cisco IOS and IOS XE
StatusVersions
AffectedCisco IOS and IOS XE

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

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.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

  • CISA added CVE-2018-0155 to its Known Exploited Vulnerabilities (KEV) catalog on 3 Mar 2022.
  • CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
  • The due date CISA sets for the required action is 17 Mar 2022.
  • The CVE record was published on 28 Mar 2018, 1,436 days before it was added to KEV.
  • The CVE record carries a CVSS v3.1 base score of 8.6 (High), taken from CISA's enrichment of the record.
  • FIRST's EPSS model puts the probability of exploitation in the next 30 days at 7.7% (percentile 94.6), as of 28 Oct 2026.
  • CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact partial.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

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: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

DateEvent
28 Mar 2018CVE record published
3 Mar 2022Added to CISA KEV
17 Mar 2022CISA due date for the required action
12 Jan 2026CVE record last updated

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