Vulnerability Monitor

The vendors, products, and vulnerabilities you care about

CVE-2017-12240

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.

Security Impact Summary

This vulnerability carries a CRITICAL severity rating with a CVSS v3.1 score of 9.8, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts confidentiality (data exposure), integrity (unauthorized modifications), and availability (service disruption) for affected systems. Impacting 265 products from cisco, from cisco, from cisco and 262 others, organizations running these solutions should prioritize assessment and patching.

Historical Context

First disclosed in 2017, this vulnerability was reported during a period defined by widespread IoT adoption challenges, mobile security concerns, and the emergence of advanced persistent threat (APT) techniques. Contemporary mitigation strategies focused on secure development practices and third-party component vetting.

Published

2017-09-29T01:34:49.077

Last Modified

2026-01-12T22:16:01.103

Status

Deferred

Source

[email protected]

Severity

CVSSv3.1: 9.8 (CRITICAL)

CVSSv2 Vector

AV:N/AC:L/Au:N/C:C/I:C/A:C

Access Vector: NETWORK
Access Complexity: LOW
Authentication: NONE
Confidentiality Impact: COMPLETE
Integrity Impact: COMPLETE
Availability Impact: COMPLETE

Exploitability Score

10.0

Impact Score

10.0

Weaknesses

Type: Secondary
CWE-20
Type: Primary
CWE-119

Affected Vendors & Products

Type	Vendor	Product	Version/Range	Vulnerable?
Operating System	cisco	ios	≤ 15.6	Yes
Hardware	cisco	1000_integrated_services_router	-	No
Hardware	cisco	1100-4g_integrated_services_router	-	No
Hardware	cisco	1100-4gltegb_integrated_services_router	-	No
Hardware	cisco	1100-4gltena_integrated_services_router	-	No
Hardware	cisco	1100-4p_integrated_services_router	-	No
Hardware	cisco	1100-6g_integrated_services_router	-	No
Hardware	cisco	1100-8p_integrated_services_router	-	No
Hardware	cisco	1100-lte_integrated_services_router	-	No
Hardware	cisco	1100_integrated_services_router	-	No
Hardware	cisco	1101-4p_integrated_services_router	-	No
Hardware	cisco	1101_integrated_services_router	-	No
Hardware	cisco	1109-2p_integrated_services_router	-	No
Hardware	cisco	1109-4p_integrated_services_router	-	No
Hardware	cisco	1109_integrated_services_router	-	No
Hardware	cisco	1111x-8p_integrated_services_router	-	No
Hardware	cisco	1111x_integrated_services_router	-	No
Hardware	cisco	111x_integrated_services_router	-	No
Hardware	cisco	1120_integrated_services_router	-	No
Hardware	cisco	1131_integrated_services_router	-	No
Hardware	cisco	1160_integrated_services_router	-	No
Hardware	cisco	1801_integrated_service_router	-	No
Hardware	cisco	1802_integrated_service_router	-	No
Hardware	cisco	1803_integrated_service_router	-	No
Hardware	cisco	1811_integrated_service_router	-	No
Hardware	cisco	1812_integrated_service_router	-	No
Hardware	cisco	1841_integrated_service_router	-	No
Hardware	cisco	1861_integrated_service_router	-	No
Hardware	cisco	1905_integrated_services_router	-	No
Hardware	cisco	1906c_integrated_services_router	-	No
Hardware	cisco	1921_integrated_services_router	-	No
Hardware	cisco	1941_integrated_services_router	-	No
Hardware	cisco	1941w_integrated_services_router	-	No
Hardware	cisco	4000_integrated_services_router	-	No
Hardware	cisco	422_integrated_services_router	-	No
Hardware	cisco	4221_integrated_services_router	-	No
Hardware	cisco	8101-32fh	-	No
Hardware	cisco	8101-32h	-	No
Hardware	cisco	8102-64h	-	No
Hardware	cisco	8201	-	No
Hardware	cisco	8201-32fh	-	No
Hardware	cisco	8202	-	No
Hardware	cisco	8208	-	No
Hardware	cisco	8212	-	No
Hardware	cisco	8218	-	No
Hardware	cisco	8800_12-slot	-	No
Hardware	cisco	8800_18-slot	-	No
Hardware	cisco	8800_4-slot	-	No
Hardware	cisco	8800_8-slot	-	No
Hardware	cisco	8804	-	No
Hardware	cisco	8808	-	No
Hardware	cisco	8812	-	No
Hardware	cisco	8818	-	No
Hardware	cisco	8831	-	No
Hardware	cisco	9800-40	-	No
Hardware	cisco	9800-80	-	No
Hardware	cisco	9800-cl	-	No
Hardware	cisco	9800-l	-	No
Hardware	cisco	asr_1000	-	No
Hardware	cisco	asr_1000-esp100	-	No
Hardware	cisco	asr_1000-esp100-x	-	No
Hardware	cisco	asr_1000-esp200-x	-	No
Hardware	cisco	asr_1000-x	-	No
Hardware	cisco	asr_1001	-	No
Hardware	cisco	asr_1001-hx	-	No
Hardware	cisco	asr_1001-hx_r	-	No
Hardware	cisco	asr_1001-x	-	No
Hardware	cisco	asr_1001-x_r	-	No
Hardware	cisco	asr_1002	-	No
Hardware	cisco	asr_1002-hx	-	No
Hardware	cisco	asr_1002-hx_r	-	No
Hardware	cisco	asr_1002-x	-	No
Hardware	cisco	asr_1002-x_r	-	No
Hardware	cisco	asr_1004	-	No
Hardware	cisco	asr_1006	-	No
Hardware	cisco	asr_1006-x	-	No
Hardware	cisco	asr_1009-x	-	No
Hardware	cisco	asr_1013	-	No
Hardware	cisco	asr_1023	-	No
Hardware	cisco	asr_900	-	No
Hardware	cisco	asr_9000	-	No
Hardware	cisco	asr_9000v	-	No
Hardware	cisco	asr_9001	-	No
Hardware	cisco	asr_9006	-	No
Hardware	cisco	asr_901-12c-f-d	-	No
Hardware	cisco	asr_901-12c-ft-d	-	No
Hardware	cisco	asr_901-4c-f-d	-	No
Hardware	cisco	asr_901-4c-ft-d	-	No
Hardware	cisco	asr_901-6cz-f-a	-	No
Hardware	cisco	asr_901-6cz-f-d	-	No
Hardware	cisco	asr_901-6cz-fs-a	-	No
Hardware	cisco	asr_901-6cz-fs-d	-	No
Hardware	cisco	asr_901-6cz-ft-a	-	No
Hardware	cisco	asr_901-6cz-ft-d	-	No
Hardware	cisco	asr_9010	-	No
Hardware	cisco	asr_901s-2sg-f-ah	-	No
Hardware	cisco	asr_901s-2sg-f-d	-	No
Hardware	cisco	asr_901s-3sg-f-ah	-	No
Hardware	cisco	asr_901s-3sg-f-d	-	No
Hardware	cisco	asr_901s-4sg-f-d	-	No
Hardware	cisco	asr_902	-	No
Hardware	cisco	asr_902u	-	No
Hardware	cisco	asr_903	-	No
Hardware	cisco	asr_907	-	No
Hardware	cisco	asr_914	-	No
Hardware	cisco	asr_920-10sz-pd	-	No
Hardware	cisco	asr_920-10sz-pd_r	-	No
Hardware	cisco	asr_920-10sz-pd_router	-	No
Hardware	cisco	asr_920-12cz-a	-	No
Hardware	cisco	asr_920-12cz-a_r	-	No
Hardware	cisco	asr_920-12cz-a_router	-	No
Hardware	cisco	asr_920-12cz-d	-	No
Hardware	cisco	asr_920-12cz-d_r	-	No
Hardware	cisco	asr_920-12cz-d_router	-	No
Hardware	cisco	asr_920-12sz-im	-	No
Hardware	cisco	asr_920-12sz-im_r	-	No
Hardware	cisco	asr_920-12sz-im_router	-	No
Hardware	cisco	asr_920-24sz-im	-	No
Hardware	cisco	asr_920-24sz-im_r	-	No
Hardware	cisco	asr_920-24sz-im_router	-	No
Hardware	cisco	asr_920-24sz-m	-	No
Hardware	cisco	asr_920-24sz-m_r	-	No
Hardware	cisco	asr_920-24sz-m_router	-	No
Hardware	cisco	asr_920-24tz-m	-	No
Hardware	cisco	asr_920-24tz-m_r	-	No
Hardware	cisco	asr_920-24tz-m_router	-	No
Hardware	cisco	asr_920-4sz-a	-	No
Hardware	cisco	asr_920-4sz-a_r	-	No
Hardware	cisco	asr_920-4sz-a_router	-	No
Hardware	cisco	asr_920-4sz-d	-	No
Hardware	cisco	asr_920-4sz-d_r	-	No
Hardware	cisco	asr_920-4sz-d_router	-	No
Hardware	cisco	asr_920u-12sz-im	-	No
Hardware	cisco	asr_9901	-	No
Hardware	cisco	asr_9902	-	No
Hardware	cisco	asr_9903	-	No
Hardware	cisco	asr_9904	-	No
Hardware	cisco	asr_9906	-	No
Hardware	cisco	asr_9910	-	No
Hardware	cisco	asr_9912	-	No
Hardware	cisco	asr_9920	-	No
Hardware	cisco	asr_9922	-	No
Hardware	cisco	catalyst_3650	-	No
Hardware	cisco	catalyst_3650-12x48fd-e	-	No
Hardware	cisco	catalyst_3650-12x48fd-l	-	No
Hardware	cisco	catalyst_3650-12x48fd-s	-	No
Hardware	cisco	catalyst_3650-12x48uq	-	No
Hardware	cisco	catalyst_3650-12x48uq-e	-	No
Hardware	cisco	catalyst_3650-12x48uq-l	-	No
Hardware	cisco	catalyst_3650-12x48uq-s	-	No
Hardware	cisco	catalyst_3650-12x48ur	-	No
Hardware	cisco	catalyst_3650-12x48ur-e	-	No
Hardware	cisco	catalyst_3650-12x48ur-l	-	No
Hardware	cisco	catalyst_3650-12x48ur-s	-	No
Hardware	cisco	catalyst_3650-12x48uz	-	No
Hardware	cisco	catalyst_3650-12x48uz-e	-	No
Hardware	cisco	catalyst_3650-12x48uz-l	-	No
Hardware	cisco	catalyst_3650-12x48uz-s	-	No
Hardware	cisco	catalyst_3650-24pd	-	No
Hardware	cisco	catalyst_3650-24pd-e	-	No
Hardware	cisco	catalyst_3650-24pd-l	-	No
Hardware	cisco	catalyst_3650-24pd-s	-	No
Hardware	cisco	catalyst_3650-24pdm	-	No
Hardware	cisco	catalyst_3650-24pdm-e	-	No
Hardware	cisco	catalyst_3650-24pdm-l	-	No
Hardware	cisco	catalyst_3650-24pdm-s	-	No
Hardware	cisco	catalyst_3650-24ps-e	-	No
Hardware	cisco	catalyst_3650-24ps-l	-	No
Hardware	cisco	catalyst_3650-24ps-s	-	No
Hardware	cisco	catalyst_3650-24td-e	-	No
Hardware	cisco	catalyst_3650-24td-l	-	No
Hardware	cisco	catalyst_3650-24td-s	-	No
Hardware	cisco	catalyst_3650-24ts-e	-	No
Hardware	cisco	catalyst_3650-24ts-l	-	No
Hardware	cisco	catalyst_3650-24ts-s	-	No
Hardware	cisco	catalyst_3650-48fd-e	-	No
Hardware	cisco	catalyst_3650-48fd-l	-	No
Hardware	cisco	catalyst_3650-48fd-s	-	No
Hardware	cisco	catalyst_3650-48fq	-	No
Hardware	cisco	catalyst_3650-48fq-e	-	No
Hardware	cisco	catalyst_3650-48fq-l	-	No
Hardware	cisco	catalyst_3650-48fq-s	-	No
Hardware	cisco	catalyst_3650-48fqm	-	No
Hardware	cisco	catalyst_3650-48fqm-e	-	No
Hardware	cisco	catalyst_3650-48fqm-l	-	No
Hardware	cisco	catalyst_3650-48fqm-s	-	No
Hardware	cisco	catalyst_3650-48fs-e	-	No
Hardware	cisco	catalyst_3650-48fs-l	-	No
Hardware	cisco	catalyst_3650-48fs-s	-	No
Hardware	cisco	catalyst_3650-48pd-e	-	No
Hardware	cisco	catalyst_3650-48pd-l	-	No
Hardware	cisco	catalyst_3650-48pd-s	-	No
Hardware	cisco	catalyst_3650-48pq-e	-	No
Hardware	cisco	catalyst_3650-48pq-l	-	No
Hardware	cisco	catalyst_3650-48pq-s	-	No
Hardware	cisco	catalyst_3650-48ps-e	-	No
Hardware	cisco	catalyst_3650-48ps-l	-	No
Hardware	cisco	catalyst_3650-48ps-s	-	No
Hardware	cisco	catalyst_3650-48td-e	-	No
Hardware	cisco	catalyst_3650-48td-l	-	No
Hardware	cisco	catalyst_3650-48td-s	-	No
Hardware	cisco	catalyst_3650-48tq-e	-	No
Hardware	cisco	catalyst_3650-48tq-l	-	No
Hardware	cisco	catalyst_3650-48tq-s	-	No
Hardware	cisco	catalyst_3650-48ts-e	-	No
Hardware	cisco	catalyst_3650-48ts-l	-	No
Hardware	cisco	catalyst_3650-48ts-s	-	No
Hardware	cisco	catalyst_3650-8x24pd-e	-	No
Hardware	cisco	catalyst_3650-8x24pd-l	-	No
Hardware	cisco	catalyst_3650-8x24pd-s	-	No
Hardware	cisco	catalyst_3650-8x24uq	-	No
Hardware	cisco	catalyst_3650-8x24uq-e	-	No
Hardware	cisco	catalyst_3650-8x24uq-l	-	No
Hardware	cisco	catalyst_3650-8x24uq-s	-	No
Hardware	cisco	catalyst_3850	-	No
Hardware	cisco	catalyst_3850-12s-e	-	No
Hardware	cisco	catalyst_3850-12s-s	-	No
Hardware	cisco	catalyst_3850-12x48u	-	No
Hardware	cisco	catalyst_3850-12xs-e	-	No
Hardware	cisco	catalyst_3850-12xs-s	-	No
Hardware	cisco	catalyst_3850-16xs-e	-	No
Hardware	cisco	catalyst_3850-16xs-s	-	No
Hardware	cisco	catalyst_3850-24p-e	-	No
Hardware	cisco	catalyst_3850-24p-l	-	No
Hardware	cisco	catalyst_3850-24p-s	-	No
Hardware	cisco	catalyst_3850-24pw-s	-	No
Hardware	cisco	catalyst_3850-24s-e	-	No
Hardware	cisco	catalyst_3850-24s-s	-	No
Hardware	cisco	catalyst_3850-24t-e	-	No
Hardware	cisco	catalyst_3850-24t-l	-	No
Hardware	cisco	catalyst_3850-24t-s	-	No
Hardware	cisco	catalyst_3850-24u	-	No
Hardware	cisco	catalyst_3850-24u-e	-	No
Hardware	cisco	catalyst_3850-24u-l	-	No
Hardware	cisco	catalyst_3850-24u-s	-	No
Hardware	cisco	catalyst_3850-24xs	-	No
Hardware	cisco	catalyst_3850-24xs-e	-	No
Hardware	cisco	catalyst_3850-24xs-s	-	No
Hardware	cisco	catalyst_3850-24xu	-	No
Hardware	cisco	catalyst_3850-24xu-e	-	No
Hardware	cisco	catalyst_3850-24xu-l	-	No
Hardware	cisco	catalyst_3850-24xu-s	-	No
Hardware	cisco	catalyst_3850-32xs-e	-	No
Hardware	cisco	catalyst_3850-32xs-s	-	No
Hardware	cisco	catalyst_3850-48f-e	-	No
Hardware	cisco	catalyst_3850-48f-l	-	No
Hardware	cisco	catalyst_3850-48f-s	-	No
Hardware	cisco	catalyst_3850-48p-e	-	No
Hardware	cisco	catalyst_3850-48p-l	-	No
Hardware	cisco	catalyst_3850-48p-s	-	No
Hardware	cisco	catalyst_3850-48pw-s	-	No
Hardware	cisco	catalyst_3850-48t-e	-	No
Hardware	cisco	catalyst_3850-48t-l	-	No
Hardware	cisco	catalyst_3850-48t-s	-	No
Hardware	cisco	catalyst_3850-48u	-	No
Hardware	cisco	catalyst_3850-48u-e	-	No
Hardware	cisco	catalyst_3850-48u-l	-	No
Hardware	cisco	catalyst_3850-48u-s	-	No
Hardware	cisco	catalyst_3850-48xs	-	No
Hardware	cisco	catalyst_3850-48xs-e	-	No
Hardware	cisco	catalyst_3850-48xs-f-e	-	No
Hardware	cisco	catalyst_3850-48xs-f-s	-	No
Hardware	cisco	catalyst_3850-48xs-s	-	No
Hardware	cisco	catalyst_3850-nm-2-40g	-	No
Hardware	cisco	catalyst_3850-nm-8-10g	-	No

References

http://www.securityfocus.com/bid/101034 Broken Link, Third Party Advisory, VDB Entry ([email protected])
http://www.securitytracker.com/id/1039445 Broken Link, Third Party Advisory, VDB Entry ([email protected])
https://quickview.cloudapps.cisco.com/quickview/bug/CSCsm45390 Vendor Advisory ([email protected])
https://quickview.cloudapps.cisco.com/quickview/bug/CSCuw77959 Vendor Advisory ([email protected])
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-dhcp Vendor Advisory ([email protected])
http://www.securityfocus.com/bid/101034 Broken Link, Third Party Advisory, VDB Entry (af854a3a-2127-422b-91ae-364da2661108)
http://www.securitytracker.com/id/1039445 Broken Link, Third Party Advisory, VDB Entry (af854a3a-2127-422b-91ae-364da2661108)
https://quickview.cloudapps.cisco.com/quickview/bug/CSCsm45390 Vendor Advisory (af854a3a-2127-422b-91ae-364da2661108)
https://quickview.cloudapps.cisco.com/quickview/bug/CSCuw77959 Vendor Advisory (af854a3a-2127-422b-91ae-364da2661108)
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-dhcp Vendor Advisory (af854a3a-2127-422b-91ae-364da2661108)
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-12240 (134c704f-9b21-4f2e-91b3-4a467353bcc0)

How SecUtils Interprets This CVE

SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For cisco's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.