Contiki-NG tinyDTLS Buffer Over-Read / Denial Of Service

An issue was discovered in Contiki-NG tinyDTLS versions through 2018-08-30. 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.

attackers buffer bug cipher denial of service handling handshake issue length loop malformed message service