CVE-2019-6473: An invalid hostname option can cause the kea-dhcp4 server to terminate
  • 28 Aug 2019
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CVE-2019-6473: An invalid hostname option can cause the kea-dhcp4 server to terminate

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Article summary

CVE: CVE-2019-6473

Document Version: 2.0

Posting date: 28 August 2019

Program Impacted: Kea DHCP

Versions affected: 1.4.0 -> 1.5.0. Versions prior to 1.4.0 are considered "End of Life" and have not been tested for this vulnerability, though they are believed to be affected. Also affects development versions 1.6.0-beta1 and 1.6.0-beta2

Severity: Medium

Exploitable: From adjacent networks permitted to relay DHCP traffic to the Kea server


An invalid hostname option can trigger an assertion failure in the Kea DHCPv4 server process (kea-dhcp4), causing the server process to exit.


An attacker who is able to deliberately exploit this vulnerability can cause the kea-dhcp4 server to stop executing, resulting in denial of service to clients. Only the DHCPv4 service is affected by this vulnerability.

CVSS Score: 6.5


For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit:



Active exploits:

No known active exploits


Upgrade to a version of Kea containing a fix, available via

  • Kea 1.4.0-P2
  • Kea 1.5.0-P1
  • Kea 1.6.0


Document Revision History:

1.0 Advance Notification, 21 August 2019
2.0 Public disclosure, 28 August 2019

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