CVE-2026-49868
9.8CriticalPublished 16 Oct 2026 · NVD status: Deferred · AI triage by gemini-3.8-flash
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Impact
- Full C/I/A compromise
- Weakness
- CWE-125, CWE-191
Impact
A rogue or compromised DHCPv6 server can crash devices or potentially expose and corrupt memory via out-of-bounds heap reads. The attacker only needs local network access to reply to DHCPv6 requests from devices running MODULE_DHCPV6_CLIENT_IA_PD.
Root cause
The DHCPv6 client parser omits minimum-length validation on IA_PD and IA_NA options, causing an integer underflow and out-of-bounds heap read.
Affected systems
RIOT OS versions prior to 2026.07
CVSS v3.1 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Fix & remediation
Upgrade RIOT OS to version 2026.07. If an immediate upgrade is not possible, disable the MODULE_DHCPV6_CLIENT_IA_PD module in the application build configuration.
$ git checkout 2026.07AI-suggested. Run it in staging first and check it against the vendor advisory. Why?
NVD description
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.