CVE-2016-6261: Canonical Ubuntu Linux

High severity, CVSS 7.5. EPSS: 3.9% chance of exploitation in the next 30 days.

The idna_to_ascii_4i function in lib/idna.c in libidn before 1.33 allows context-dependent attackers to cause a denial of service (out-of-bounds read and crash) via 64 bytes of input.

Affected products

• Canonical Ubuntu Linux: version 12.04 only; version 14.04 only; version 16.04 only
• GNU Libidn: up to and including 1.32
• Opensuse Leap: version 42.1 only

Published 2016-09-07. Last modified 2026-06-17.