RIOT is an open-source microcontroller operating system, designed to match the requirements of Internet of Things (IoT) devices and other embedded devices. In version 2025.10 and prior, multiple out-of-bounds read allow any unauthenticated user, with ability to send or manipulate input packets, to read adjacent memory locations, or crash a vulnerable device running the 6LoWPAN stack. The received packet is cast into a sixlowpan_sfr_rfrag_t struct and dereferenced without validating the packet is large enough to contain the struct object. At time of publication, no known patch exists.
RIOT OS versions up to and including 2026.01-devel-317 contain a stack-based buffer overflow vulnerability in the tapslip6 utility. The vulnerability is caused by unsafe string concatenation in the devopen() function, which constructs a device path using unbounded user-controlled input. The utility uses strcpy() and strcat() to concatenate the fixed prefix '/dev/' with a user-supplied device name provided via the -s command-line option without bounds checking. This allows an attacker to supply an excessively long device name and overflow a fixed-size stack buffer, leading to process crashes and memory corruption.
RIOT OS versions up to and including 2026.01-devel-317 contain a stack-based buffer overflow vulnerability in the ethos utility due to missing bounds checking when processing incoming serial frame data. The vulnerability occurs in the _handle_char() function, where incoming frame bytes are appended to a fixed-size stack buffer without verifying that the current write index remains within bounds. An attacker capable of sending crafted serial or TCP-framed input can cause the current write index to exceed the buffer size, resulting in a write past the end of the stack buffer. This condition leads to memory corruption and application crash.
RIOT is an open-source microcontroller operating system, designed to match the requirements of Internet of Things (IoT) devices and other embedded devices. A vulnerability was discovered in the IPv6 fragmentation reassembly implementation of RIOT OS v2025.07. When copying the contents of the first fragment (offset=0) into the reassembly buffer, no size check is performed. It is possible to force the creation of a small reassembly buffer by first sending a shorter fragment (also with offset=0). Overflowing the reassembly buffer corrupts the state of other packet buffers which an attacker might be able to used to achieve further memory corruption (potentially resulting in remote code execution). To trigger the vulnerability, the `gnrc_ipv6_ext_frag` module must be included and the attacker must be able to send arbitrary IPv6 packets to the victim. Version 2025.10 fixes the issue.
RIOT is an open-source microcontroller operating system, designed to match the requirements of Internet of Things (IoT) devices and other embedded devices. A vulnerability was discovered in the IPv6 fragmentation reassembly implementation of RIOT OS v2025.07. When receiving an fragmented IPv6 packet with fragment offset 0 and an empty payload, the payload pointer is set to NULL. However, the implementation still tries to copy the payload into the reassembly buffer, resulting in a NULL pointer dereference which crashes the OS (DoS). To trigger the vulnerability, the `gnrc_ipv6_ext_frag` module must be enabled and the attacker must be able to send arbitrary IPv6 packets to the victim. RIOT OS v2025.10 fixes the issue.
RIOT-OS, an operating system that supports Internet of Things devices, has an ineffective size check implemented with `assert()` can lead to buffer overflow in versions up to and including 2025.04. Assertions are usually compiled out in production builds. If assertions are the only defense against untrusted inputs, the software may be exposed to attacks that utilize the lack of proper input checks. In the `l2filter_add()` function shown below, `addr_len` is checked using an assertion and is subsequently used as an argument in a `memcpy()` call. When assertions are disabled, there would be no size check for `addr_len`. As a consequence, if an attacker were to provide an `addr_len` value larger than `CONFIG_L2FILTER_ADDR_MAXLEN`, they can trigger a buffer overflow and write past the `list[i].addr` buffer. If the unchecked input is attacker-controlled, the impact of the buffer overflow can range from a denial of service to arbitrary code execution. Commit f6f7de4ccc107c018630e4c15500825caf02e1c2 contains a patch for the vulnerability.
RIOT is an open-source microcontroller operating system, designed to match the requirements of Internet of Things (IoT) devices and other embedded devices. A malicious actor can send a IEEE 802.15.4 packet with spoofed length byte and optionally spoofed FCS, which eventually results into an endless loop on a CC2538 as receiver. Before PR #20998, the receiver would check for the location of the CRC bit using the packet length byte by considering all 8 bits, instead of discarding bit 7, which is what the radio does. This then results into reading outside of the RX FIFO. Although it prints an error when attempting to read outside of the RX FIFO, it will continue doing this. This may lead to a discrepancy in the CRC check according to the firmware and the radio. If the CPU judges the CRC as correct and the radio is set to `AUTO_ACK`, when the packet requests and acknowledgment the CPU will go into the state `CC2538_STATE_TX_ACK`. However, if the radio judged the CRC as incorrect, it will not send an acknowledgment, and thus the `TXACKDONE` event will not fire. It will then never return to the state `CC2538_STATE_READY` since the baseband processing is still disabled. Then the CPU will be in an endless loop. Since setting to idle is not forced, it won't do it if the radio's state is not `CC2538_STATE_READY`. A fix has not yet been made.