An issue was discovered in Contiki through 3.0 and Contiki-NG through 4.5. The code for parsing Type A domain name answers in ip64-dns64.c doesn't verify whether the address in the answer's length is sane. Therefore, when copying an address of an arbitrary length, a buffer overflow can occur. This bug can be exploited whenever NAT64 is enabled.

An issue was discovered in uIP through 1.0, as used in Contiki and Contiki-NG. Domain name parsing lacks bounds checks, allowing an attacker to corrupt memory with crafted DNS packets.

The code that processes DNS responses in uIP through 1.0, as used in Contiki and Contiki-NG, does not check whether the number of responses specified in the DNS packet header corresponds to the response data available in the DNS packet, leading to an out-of-bounds read and Denial-of-Service in resolv.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.

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 snmp_oid_decode_oid() may overwrite memory areas beyond the provided target buffer, when called from snmp_message_decode() 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 bulk get request response encoding function. 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. When a bulk get request response is assembled, a stack buffer dedicated for OIDs (with a limited capacity) is allocated in snmp_engine_get_bulk(). When snmp_engine_get_bulk() is populating the stack buffer, an overflow condition may occur due to lack of input length validation. This makes it possible to overwrite stack regions beyond the allocated buffer, including the return address from the function. As a result, the code execution path may be redirected to an address provided in the SNMP bulk get payload. If the target architecture uses common addressing space for program and data memory, it may also be possible to supply code in the SNMP request payload, and redirect the execution path to the remotely injected code, by modifying the function's return address.

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.

Open-iSCSI: counter wraparound resulting in infinite loop

An issue was discovered in Contiki through 3.0. An Integer Overflow exists in the uIP TCP/IP Stack component when parsing TCP MSS options of IPv4 network packets in uip_process in net/ipv4/uip.c.

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 snmp_ber_decode_string_len_buffer in os/net/app-layer/snmp/snmp-ber.c.

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.

An issue was discovered in Contiki-NG through 4.3 and Contiki through 3.0. A buffer overflow is present due to an integer underflow during 6LoWPAN fragment processing in the face of truncated fragments in os/net/ipv6/sicslowpan.c. This results in accesses of unmapped memory, crashing the application. An attacker can cause a denial-of-service via a crafted 6LoWPAN frame.

An issue was discovered in Contiki-NG through 4.3 and Contiki through 3.0. An out of bounds write is present in the data section during 6LoWPAN fragment re-assembly in the face of forged fragment offsets in os/net/ipv6/sicslowpan.c.

An issue was discovered in the MQTT server in Contiki-NG before 4.2. The function parse_publish_vhdr() that parses MQTT PUBLISH messages with a variable length header uses memcpy to input data into a fixed size buffer. The allocated buffer can fit only MQTT_MAX_TOPIC_LENGTH (default 64) bytes, and a length check is missing. This could lead to Remote Code Execution via a stack-smashing attack (overwriting the function return address). Contiki-NG does not separate the MQTT server from other servers and the OS modules, so access to all memory regions is possible.

An issue was discovered in Contiki-NG through 4.1. There is a buffer over-read in lookup in os/storage/antelope/lvm.c while parsing AQL (lvm_register_variable, lvm_set_variable_value, create_intersection, create_union).

An issue was discovered in Contiki-NG through 4.1. There is a stack-based buffer overflow in next_string in os/storage/antelope/aql-lexer.c while parsing AQL (parsing next string).

An issue was discovered in Contiki-NG through 4.1. There is a buffer overflow while parsing AQL in lvm_shift_for_operator in os/storage/antelope/lvm.c.

An issue was discovered in Contiki-NG through 4.1. There is a buffer overflow in lvm_set_type in os/storage/antelope/lvm.c while parsing AQL (lvm_set_op, lvm_set_relation, lvm_set_operand).

An issue was discovered in Contiki-NG through 4.1. There is a stack-based buffer overflow in parse_relations in os/storage/antelope/aql-parser.c while parsing AQL (storage of relations).

contiki-ng version 4 contains a Buffer Overflow vulnerability in AQL (Antelope Query Language) database engine that can result in Attacker can perform Remote Code Execution on device using Contiki-NG operating system. This attack appear to be exploitable via Attacker must be able to run malicious AQL code (e.g. via SQL-like Injection attack).