CVE-2018-0173

HIGH

8.6

CVSS Score

Published: March 28, 2018 at 10:00 PM UTC

Updated: June 17, 2026 at 01:30 AM UTC

14 products affected across 1 vendorIOSIOS XeAsr 1002-x· also runs on 6 platforms

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Severity

HIGH8.6

Exploitation

CISA KEV

Exploit prediction

EPSS 8%

SSVC

Active

Actively Exploited

CISA Known Exploited Vulnerabilities (KEV) Catalog

EPSS Score7.6%

EPSS (Exploit Prediction Scoring System) estimates a 7.6% chance this CVE is exploited in the wild within the next 30 days — higher than 95% of all CVEs. It complements CVSS: a high EPSS on a mid-severity CVE can still be urgent.

A vulnerability in the Cisco IOS Software and Cisco IOS XE Software function that restores encapsulated option 82 information in DHCP Version 4 (DHCPv4) packets can allow for denial-of-service (DoS).

Required Action

Apply updates per vendor instructions.

Ransomware Use

Unknown

Added to KEV

Mar 3, 2022

Remediation Due

Mar 17, 2022

1687 days overdue

Notes

https://nvd.nist.gov/vuln/detail/CVE-2018-0173

Description

A vulnerability in the Cisco IOS Software and Cisco IOS XE Software function that restores encapsulated option 82 information in DHCP Version 4 (DHCPv4) packets could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a Relay Reply denial of service (DoS) condition. The vulnerability exists because the affected software performs incomplete input validation of encapsulated option 82 information that it receives in DHCPOFFER messages from DHCPv4 servers. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device, which the device would then forward to a DHCPv4 server. When the affected software processes the option 82 information that is encapsulated in the response from the server, an error could occur. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCvg62754.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

IOS · Cisconpm

95%

v ≤ 15.2(4a)ea5v ≤ 15.2(6)e0adenali-16.3.4

cisco-4321-integrated-services-router (environment) · cisco-4331-integrated-services-router (environment) · cisco-4351-integrated-services-router (environment) · cisco-4431-integrated-services-router (environment) · cisco-4451-x-integrated-services-router (environment) · cisco-asr-1000-series-route-processor-rp2 (environment) · cisco-asr-1000-series-route-processor-rp3 (environment) · cisco-asr-1001-hx (environment) · cisco-asr-1001-x (environment) · cisco-asr-1002-hx (environment) · cisco-asr-1002-x (environment) · cisco-cloud-services-router-1000v (environment) · rockwellautomation-allen-bradley-armorstratix-5700 (environment) · rockwellautomation-allen-bradley-stratix-5400 (environment) · rockwellautomation-allen-bradley-stratix-5410 (environment) · rockwellautomation-allen-bradley-stratix-5700 (environment) · rockwellautomation-allen-bradley-stratix-8000 (environment) · rockwellautomation-allen-bradley-stratix-8300 (environment)

IOS Xe · Cisco

95%

v ≤ 15.2(4a)ea5v ≤ 15.2(6)e0adenali-16.3.4

4321 Integrated Services Router · Ciscodevice

80%

All versions

4331 Integrated Services Router · Ciscodevice

80%

All versions

4351 Integrated Services Router · Ciscodevice

80%

All versions