CVE-2021-42143: Contiki-NG Tinydtls

Critical severity, CVSS 9.1. EPSS: 0.8% chance of exploitation in the next 30 days.

An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. An infinite loop bug exists during the handling of a ClientHello handshake message. This bug allows remote attackers to cause a denial of service by sending a malformed ClientHello handshake message with an odd length of cipher suites, which triggers an infinite loop (consuming all resources) and a buffer over-read that can disclose sensitive information.

Affected products

• Contiki-NG Tinydtls: up to and including 2018-08-30

Published 2024-01-24. Last modified 2026-06-17.