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CVE-2017-12240

CWE-20

Critical

102.2

RPS

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.

Source: NVD

Signals

CVSS
9.8
Critical · v3.1
EPSS
13.77%
Probability of exploitation in the next 30 days (FIRST)
CISA KEV
In CISA KEV since Mar 2022
Fix commit
No known fix commit
Sources: MoreFixes, FreshFixes
Weakness
CWE-20
CWE-20, CWE-119
Published
29 Sept 2017
Last modified 21 Apr 2026

How to read these signals: RPS · EPSS · CISA KEV · Data sources

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Data as of 8 Oct 2026, 05:16 UK time