VULNERABILITY INTELLIGENCE

CVE-2017-12240

CVSS score9.8 CRITICAL
EPSS probability13.77%
CISA KEVKnown exploited vulnerability
Published2017-09-29
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Known Exploited Vulnerability

Cisco IOS and IOS XE Software DHCP Remote Code Execution Vulnerability

Vendor / product: Cisco / IOS and IOS XE Software

Description

The DHCP relay subsystem of Cisco IOS 12.2 through 15.6 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. The attacker could also cause an affected system to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to a buffer overflow condition in the DHCP relay subsystem of the affected software. An attacker could exploit this vulnerability by sending a crafted DHCP Version 4 (DHCPv4) packet to an affected system. A successful exploit could allow the attacker to execute arbitrary code and gain full control of the affected system or cause the affected system to reload, resulting in a DoS condition. Cisco Bug IDs: CSCsm45390, CSCuw77959.

Weakness classification

  • CWE-20: Improper Input Validation
  • CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

Primary references