An issue was discovered in the IPv6 stack in Contiki through 3.0. There are inconsistent checks for IPv6 header extension lengths. This leads to Denial-of-Service and potential Remote Code Execution via a crafted ICMPv6 echo packet.
https://www.kb.cert.org/vuls/id/815128
https://us-cert.cisa.gov/ics/advisories/icsa-20-343-01
https://www.tenable.com/blog/amnesia33-researchers-disclose-33-vulnerabilities-tcpip-libraries-uip-fnet-picotcp-nutnet
Source: Mitre, NVD
Published: 2020-12-11
Updated: 2020-12-14
Named Vulnerability: AMNESIA:33
Base Score: 7.5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P
Severity: High
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
EPSS: 0.16481