7.5High KEV

CVE-2018-0156Cisco IOS Software and Cisco IOS XE Software Smart Install Denial-of-Service Vulnerability

Cisco IOS and IOS XE Published: 2018-03-29 01:00 (8 years ago)

Known exploited — Cisco IOS Software and Cisco IOS XE Software Smart Install Denial-of-Service Vulnerability

CISA confirmed this vulnerability is used in real attacks on 03.03.2022. Remediation deadline for US federal agencies: 17.03.2022.

Required action: Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2018-0156

Description

A vulnerability in the Smart Install feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper validation of packet data. An attacker could exploit this vulnerability by sending a crafted packet to an affected device on TCP port 4786. Only Smart Install client switches are affected. Cisco devices that are configured as a Smart Install director are not affected by this vulnerability. Cisco Bug IDs: CSCvd40673.

Weakness (CWE): CWE-399 CWE-20

Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.

Affected products and versions

Vendor	Product	Versions
cisco	ios	15.2(2)e4
cisco	ios xe	15.2(2)e4
—	Cisco IOS and IOS XE	Cisco IOS and IOS XE

References and patches

https://ics-cert.us-cert.gov/advisories/ICSA-18-107-04 Third Party AdvisoryUS Government Resource
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-smi Vendor Advisory
1040596 vdb-entryThird Party AdvisoryVDB Entry
103569 vdb-entryThird Party AdvisoryVDB Entry
https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05 Third Party AdvisoryUS Government Resource
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-0156 US Government Resource

CPE matches (NVD) (4)

cpe:2.3:o:cisco:ios:15.2\(2\)e4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2\(2a\)ja:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:15.2\(2\)e4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:15.2\(2a\)ja:*:*:*:*:*:*:*

CVSS score

7.5High

Source: CISA-ADP · CVSS 3.1

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

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

All scores (4)

CISA-ADP	CVSS 3.1	7.5High
nvd	CVSS 3.1	7.5High
134c704f-9b21-4f2e-91b3-4a467353bcc0	CVSS 3.1	7.5High
nvd	CVSS 2.0	7.8High

EPSS (chance of exploitation in 30 days)

9.36%

higher than 95% of all CVEs

CISA assessment (SSVC)

Exploitation: active
Automatable: yes
Technical impact: partial

Timeline

ID reserved2017-11-27
Published2018-03-29 01:00
Reached IP-DB2026-10-24 23:33
Added to KEV2022-03-03
Last updated2026-06-17 04:29

Assigned by (CNA): cisco
NVD status: Analyzed

View at source: CVE.org · NVD

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