In the TCP implementation (gnrc_tcp) in RIOT through 2019.07, the parser for TCP options does not terminate on all inputs, allowing a denial-of-service, because sys/net/gnrc/transport_layer/tcp/gnrc_tcp_option.c has an infinite loop for an unknown zero-length option.
Severity
CVSS 3.1
7.5 high
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
1.4% chance of exploitation in the next 30 days; higher than 73% of CVEs (scores of 2026-10-31)