What is CVE-2018-0171?

CVE-2018-0171 is a critical-severity vulnerability in Cisco iOS, classified under Improper Input Validation. CVSS score: 9.8/10. Published 2018-03-28.

How severe is CVE-2018-0171?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2018-0171 known to be exploited?

Yes. CVE-2018-0171 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating it is being actively exploited. 20 public proof-of-concept repositories are indexed.

Buffer overflow in Cisco iOS

CVE-2018-0171

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, or to execute arbitrary code on an affected device. The vulnerability is due to improper validation of packet data. An attacker could exploit this vulnerability by sending a crafted Smart Install message to an affected device on TCP port 4786. A successful exploit could allow the attacker to cause a buffer overflow on the affected device, which could have the following impacts: Triggering a reload of the device, Allowing the attacker to execute arbitrary code on the device, Causing an indefinite loop on the affected device that triggers a watchdog crash. Cisco Bug IDs: CSCvg76186.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.995 (99.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Cisco Ios — versions 15.2\(5\)e, 15.2(5)e
N/a Cisco Ios And Xe — versions Cisco IOS and IOS XE

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2021-11-03. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2022-05-03.

Required action: Apply updates per vendor instructions.

Public proof-of-concept exploits

References

psirt@cisco.com (US Government Resource, Third Party Advisory, x_refsource_MISC)
psirt@cisco.com (VDB Entry, Third Party Advisory, vdb-entry, x_refsource_SECTRACK)
psirt@cisco.com (x_refsource_CONFIRM, Vendor Advisory)
psirt@cisco.com (x_refsource_MISC, Press/Media Coverage)
psirt@cisco.com (US Government Resource, Third Party Advisory, x_refsource_MISC)
psirt@cisco.com (VDB Entry, Third Party Advisory, vdb-entry, x_refsource_BID)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)

Frequently asked questions

What is CVE-2018-0171?: CVE-2018-0171 is a critical-severity vulnerability in Cisco iOS, classified under Improper Input Validation. CVSS score: 9.8/10. Published 2018-03-28.
How severe is CVE-2018-0171?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2018-0171 known to be exploited?: Yes. CVE-2018-0171 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating it is being actively exploited. 20 public proof-of-concept repositories are indexed.