# 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.

- Page: https://www.vulneraibility.com/cve/CVE-2017-12240
- CVSS: 9.8
- Known exploited: yes, in CISA KEV since 2022-03-03; CISA due date 2022-03-24
- EPSS: 13.77% (percentile 96.6)
- CISA SSVC: exploitation active, automatable yes, technical impact total (assessed 2024-11-08)
- Weakness: CWE-20
- Published: 2017-09-29

## Affected versions

- Cisco IOS and IOS XE: affected Cisco IOS and IOS XE

A version outside these ranges is not a statement that it is unaffected.

## References

- [other] https://quickview.cloudapps.cisco.com/quickview/bug/CSCuw77959
- [other] https://quickview.cloudapps.cisco.com/quickview/bug/CSCsm45390
- [other] http://www.securityfocus.com/bid/101034
- [other] https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-dhcp
- [other] http://www.securitytracker.com/id/1039445
- [other] https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-12240

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.