CVE-2018-0172: Cisco IOS and IOS XE Software Improper Input Validation Vulnerability
A vulnerability in the DHCP option 82 encapsulation functionality of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition.
Published Mar 28, 2018 · Updated Jun 17, 2026
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Advisory details
From the National Vulnerability Database. This product uses the NVD API but is not endorsed or certified by the NVD.
A vulnerability in the DHCP option 82 encapsulation functionality of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability exists because the affected software performs incomplete input validation of option 82 information that it receives in DHCP Version 4 (DHCPv4) packets from DHCP relay agents. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device. A successful exploit could allow the attacker to cause a heap overflow condition on the affected device, which will cause the device to reload and result in a DoS condition. Cisco Bug IDs: CSCvg62730.
References
- https://ics-cert.us-cert.gov/advisories/ICSA-18-107-04
- https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-dhcpr1
- https://www.tenable.com/security/research/tra-2018-06
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-0172
How this page is made: the data panel comes from the GitHub Advisory Database, CISA’s KEV catalog, the NVD and FIRST EPSS, and updates twice a day. No analysis has been written for this entry yet. Methodology
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