ACTIVELY EXPLOITED
CVE-2017-12240: Cisco IOS and IOS XE Software DHCP Remote Code Execution Vulnerability
| Vendor | Cisco |
|---|---|
| Product | IOS and IOS XE Software |
| Actively exploited | Yes |
| Added to CISA KEV | 3 Mar 2022 |
| CISA federal deadline | 24 Mar 2022 |
| Weakness (CWE) | CWE-20 |
Required action (CISA's text)
Apply updates per vendor instructions.
Description (NVD)
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.
SOURCES
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- CVE-2026-76504: Cisco Catalyst SD-WAN Manager Hex Encoding Vulnerability
- CVE-2026-76460: Cisco Identity Services Engine Incorrect Use of Privileged APIs Vulnerability
Data from NVD, CISA KEV, FIRST EPSS and vendor advisories. Updated 10 Nov 2026.