CVE-2012-3955: Canonical Ubuntu Linux

High severity, CVSS 7.1. EPSS: 21.7% chance of exploitation in the next 30 days.

ISC DHCP 4.1.x before 4.1-ESV-R7 and 4.2.x before 4.2.4-P2 allows remote attackers to cause a denial of service (daemon crash) in opportunistic circumstances by establishing an IPv6 lease in an environment where the lease expiration time is later reduced.

Affected products

• Canonical Ubuntu Linux: version 10.04 only; version 11.04 only; version 11.10 only; version 12.04 only
• Debian Debian Linux: version 6.0 only; version 7.0 only
• ISC Dhcp: version 4.1-esv only; version 4.1.0 only; version 4.1.1 only; version 4.1.2 only

Published 2012-09-14. Last modified 2026-06-16.