Buffer overflows were discovered in Contiki-NG 4.4 through 4.5, in the SNMP agent. Functions parsing the OIDs in SNMP requests lack sufficient allocated target-buffer capacity verification when writing parsed OID values. The function snmpoiddecodeoid() may overwrite memory areas beyond the provided target buffer, when called from snmpmessagedecode() upon an SNMP request reception. Because the content of the write operations is externally provided in the SNMP requests, it enables a remote overwrite of an IoT device's memory regions beyond the allocated buffer. This overflow may allow remote overwrite of stack and statically allocated variables memory regions by sending a crafted SNMP request.

Buffer overflows were discovered in Contiki-NG 4.4 through 4.5, in the SNMP agent. The function parsing the received SNMP request does not verify the input message's requested variables against the capacity of the internal SNMP engine buffer. If the number of variables in the request exceeds the allocated buffer, a memory write out of the buffer boundaries occurs. This write operation provides a possibility to overwrite other variables allocated in the .bss section by the application. Because the sender of the frame is in control of the content that will be written beyond the buffer limits, and there is no strict process memory separation, this issue may allow overwriting of sensitive memory areas of an IoT device.

An out-of-bounds read in the SNMP stack in Contiki-NG 4.4 and earlier allows an attacker to cause a denial of service and potentially disclose information via crafted SNMP packets to snmpberdecodestringlenbuffer in os/net/app-layer/snmp/snmp-ber.c.

Memory access out of buffer boundaries issues was discovered in Contiki-NG 4.4 through 4.5, in the SNMP BER encoder/decoder. The length of provided input/output buffers is insufficiently verified during the encoding and decoding of data. This may lead to out-of-bounds buffer read or write access in BER decoding and encoding functions.

A buffer overflow in os/net/mac/ble/ble-l2cap.c in the BLE stack in Contiki-NG 4.4 and earlier allows an attacker to execute arbitrary code via malicious L2CAP frames.