CVE-2016-2851: Cypherpunks Libotr

Critical severity, CVSS 9.8. EPSS: 25.4% chance of exploitation in the next 30 days.

Integer overflow in proto.c in libotr before 4.1.1 on 64-bit platforms allows remote attackers to cause a denial of service (memory corruption and application crash) or execute arbitrary code via a series of large OTR messages, which triggers a heap-based buffer overflow.

Affected products

• Cypherpunks Libotr: up to and including 4.1.0
• Debian Debian Linux: version 7.0 only; version 8.0 only
• Opensuse Leap: version 42.1 only
• Opensuse Opensuse: version 13.2 only

Published 2016-04-07. Last modified 2026-06-17.