RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems. Prior to 2026.07, _parse_reply() in sys/net/application_layer/dhcpv6/client.c omits minimum-length validation before passing IA_PD and IA_NA option bodies to sub-option parsers. A malicious or compromised DHCPv6 server can send a REPLY with an option length smaller than the required structure while MODULE_DHCPV6_CLIENT_IA_PD is enabled, causing _parse_ia_pd_option to read past the option body, size_t underflow, and unbounded out-of-bounds heap reads that can crash the device and may expose or corrupt memory. This issue is fixed in version 2026.07.
Critical 9.8
CVE-2026-49868
RIOT-OS RIOT — out-of-bounds read.
RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems.
Published Updated Source NVD
CVSS 3.1
9.8
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploit chance, 30 days
0.4%
Higher than 31% of all CVEs (EPSS)
Status
No known exploitation
Not in CISA KEV
Patch
Unknown
Check the vendor advisory
What happened
What to do
- 01Check whether you run RIOT-OS RIOT, and which version.
- 02Follow the vendor advisory for a fix or a workaround.
References
Timeline · UTC
- Published to NVD
- NVD record updated
Also actively exploited
Other CVEs in RIOT-OS RIOT
2 more CVEs