RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems. In 2026.07 and earlier, _receive() in sys/net/gnrc/network_layer/sixlowpan/gnrc_sixlowpan.c can route an undersized packet into SFF fragment handling after only a minimal payload check. The code then interprets the packet as a sixlowpan_frag_t or larger fragment header without verifying that the packet snip contains the required bytes.
A remote attacker can send a malformed 6LoWPAN fragment that causes gnrc_sixlowpan_frag_recv() to read beyond the packet buffer, potentially disclosing memory and crashing the network stack. No fixed repository release is available as of this review.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v3.1