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CVE DATABASE  /  CVE-2018-0156

CVE-2018-0156

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

CVSS 7.5 · HIGH ⚠ CISA KEV — ACTIVELY EXPLOITED
On the CISA KEV catalog

Confirmed exploited in the wild. Added 2022-03-03. Federal remediation due 2022-03-17.
Required action: Apply updates per vendor instructions.

Summary

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.

CVSS 3.1 breakdown

Base score7.5 (HIGH)
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vectorNETWORK
Attack complexityLOW
Privileges requiredNONE
User interactionNONE
ScopeUNCHANGED
ConfidentialityNONE
IntegrityNONE
AvailabilityHIGH

Weakness type (CWE)

Affected products

Cisco iosCisco catalyst 2960-plus 24lc-lCisco catalyst 2960-plus 24lc-sCisco catalyst 2960-plus 24pc-lCisco catalyst 2960-plus 24pc-sCisco catalyst 2960-plus 24tc-lCisco catalyst 2960-plus 24tc-sCisco catalyst 2960-plus 48pst-lCisco catalyst 2960-plus 48pst-sCisco catalyst 2960-plus 48tc-lCisco catalyst 2960-plus 48tc-sCisco catalyst 2960c-12pc-lCisco catalyst 2960c-8pc-lCisco catalyst 2960c-8tc-lCisco catalyst 2960c-8tc-sCisco catalyst 2960cg-8tc-lCisco catalyst 2960cpd-8pt-lCisco catalyst 2960cpd-8tt-lCisco catalyst 2960s-24pd-lCisco catalyst 2960s-24ps-l
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References

Data: NIST NVD + CISA KEV. NVD last modified 2026-01-13. Always verify against the vendor advisory before acting.

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