CVE-2017-12240
Cisco IOS and IOS XE Software DHCP Remote Code Execution Vulnerability
What is affected
| Vendor | Cisco |
|---|---|
| Product | IOS and IOS XE Software |
| Weakness | CWE-20 |
The vulnerability
The Dynamic Host Configuration Protocol (DHCP) relay subsystem of Cisco IOS and Cisco IOS XE Software contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code and gain full control of an affected system.
Required action
Apply updates per vendor instructions.
US federal civilian agencies were required to act by 24 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 11 Nov 2026, 21:30. Nothing here is our own assessment. For the technical scoring, see the NVD record below.
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