CVE-2018-0172
Cisco IOS and IOS XE Software Improper Input Validation Vulnerability
What is affected
| Vendor | Cisco |
|---|---|
| Product | IOS and IOS XE Software |
| Weakness | CWE-20 |
The vulnerability
A vulnerability in the DHCP option 82 encapsulation functionality of Cisco IOS Software and Cisco IOS XE Software could allow for denial-of-service (DoS).
Required action
Apply updates per vendor instructions.
US federal civilian agencies were required to act by 17 March 2022 under BOD 22-01. The deadline is a compliance date, not a measure of severity — it says nothing about how dangerous the flaw is to anyone else.
Where this comes from
Every field on this page is taken from the CISA Known Exploited Vulnerabilities catalog, last synced 12 Nov 2026, 00:29. Nothing here is our own assessment. For the technical scoring, see the NVD record below.
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