CVE-2017-13704: Canonical Ubuntu Linux

High severity, CVSS 7.5. EPSS: 65.4% chance of exploitation in the next 30 days.

In dnsmasq before 2.78, if the DNS packet size does not match the expected size, the size parameter in a memset call gets a negative value. As it is an unsigned value, memset ends up writing up to 0xffffffff zero's (0xffffffffffffffff in 64 bit platforms), making dnsmasq crash.

Affected products

• Canonical Ubuntu Linux: version 14.04 only; version 16.04 only; version 17.04 only
• Debian Debian Linux: version 7.0 only; version 7.1 only; version 9.0 only
• Fedoraproject Fedora: version 27 only
• Novell Leap: version 42.2 only; version 42.3 only
• Red Hat Enterprise Linux Desktop: version 7.0 only
• Red Hat Enterprise Linux Server: version 7.0 only
• Red Hat Enterprise Linux Workstation: version 7.0 only
• Thekelleys Dnsmasq: up to and including 2.77

Published 2017-10-03. Last modified 2026-06-17.