Contiki-NG's MQTT client parsepublishvhdr() in os/net/app-layer/mqtt/mqtt.c sets topiclenreceived=1 before checking topiclen against the 64-byte limit, so an over-length topic returns early but leaves the flag set. On the next TCP segment, tcpinput() re-invokes the parser with topicreceived==0, and the persisted topiclenreceived==1 skips the length-reading block containing the guard, falling through directly to a memcpy() that uses the unvalidated 16-bit topiclen as the copy length. The 65-byte topic[] destination overruns into adjacent struct fields including the payloadchunk pointer, which subsequent MQTT code dereferences, giving a compromised or attacker-controlled broker an arbitrary-pointer-write primitive. Contiki-NG's MQTT implementation has no TLS support so the connection is plaintext. Impact ranges from information disclosure and denial of service to remote code execution on embedded targets without memory protection.

Contiki-NG's LwM2M TLV parser lwm2mtlvread() in os/services/lwm2m/lwm2m-tlv.c ignores its caller-supplied buffer length argument and reads up to six bytes from the input buffer with no bounds check. The caller in lwm2m-engine.c iterates while there is at least one byte remaining, so a crafted CoAP WRITE to any LwM2M endpoint whose final TLV supplies exactly one byte triggers up to five out-of-bounds reads of heap memory adjacent to the CoAP input buffer, disclosing memory contents (including key material and peer addresses) through the parsed tlv->id, tlv->length, and tlv->value fields. Corrupted tlvlen derived from the out-of-bounds memory further corrupts the caller's parse offset. In LwM2M NoSec mode, the default for constrained devices, no authentication is required.

Contiki-NG's DNS/mDNS resolver skipname() in os/services/resolv/resolv.c walks DNS wire-format name labels with no packet-boundary check, and the caller in newdata() invokes it in a loop iterating nquestions times from the attacker-controlled DNS header before validating the transaction ID. An attacker who sets nquestions higher than the number of complete questions present causes skipname() to walk past the UDP packet buffer, and the returned pointer is cast to struct dnsanswer for further memory reads. On builds with RESOLVCONFSUPPORTSMDNS enabled, any peer on the local segment can trigger the read unauthenticated via a multicast UDP 5353 packet with no outstanding query required; on standard DNS builds an attacker who can inject a UDP response from port 53 during an outstanding query can trigger the same read. Impact is out-of-bounds read of uipbuf and adjacent memory, disclosing memory contents or crashing the resolver.

Contiki-NG is an operating system for internet of things devices. In version 4.8 and prior, when processing ICMP DAO packets in the daoinputstoring function, the Contiki-NG OS does not verify that the packet buffer is big enough to contain the bytes it needs before accessing them. Up to 16 bytes can be read out of bounds in the daoinputstoring function. An attacker can truncate an ICMP packet so that it does not contain enough data, leading to an out-of-bounds read on these lines. The problem has been patched in the "develop" branch of Contiki-NG, and is expected to be included in release 4.9. As a workaround, one can apply the changes in Contiki-NG pull request #2435 to patch the system.

Contiki-NG is an open-source, cross-platform operating system for IoT devices. When reading the TCP MSS option value from an incoming packet, the Contiki-NG OS does not verify that certain buffer indices to read from are within the bounds of the IPv6 packet buffer, uipbuf. In particular, there is a 2-byte buffer read in the module os/net/ipv6/uip6.c. The buffer is indexed using 'UIPIPTCPHLEN + 2 + c' and 'UIPIPTCPHLEN + 3 + c', but the uipbuf buffer may not have enough data, resulting in a 2-byte read out of bounds. The problem has been patched in the "develop" branch of Contiki-NG, and is expected to be included in release 4.9. Users are advised to watch for the 4.9 release and to upgrade when it becomes available. There are no workarounds for this vulnerability aside from manually patching with the diff in commit cde4e9839.

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. Versions prior to 4.9 are vulnerable to an Out-of-bounds read. While processing the L2CAP protocol, the Bluetooth Low Energy stack of Contiki-NG needs to map an incoming channel ID to its metadata structure. While looking up the corresponding channel structure in getchannelforcid (in os/net/mac/ble/ble-l2cap.c), a bounds check is performed on the incoming channel ID, which is meant to ensure that the channel ID does not exceed the maximum number of supported channels.However, an integer truncation issue leads to only the lowest byte of the channel ID to be checked, which leads to an incomplete out-of-bounds check. A crafted channel ID leads to out-of-bounds memory to be read and written with attacker-controlled data. The vulnerability has been patched in the "develop" branch of Contiki-NG, and will be included in release 4.9. As a workaround, Users can apply the patch in Contiki-NG pull request 2081 on GitHub.

An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers allow remote attackers to reuse the same epoch number within two times the TCP maximum segment lifetime, which is prohibited in RFC6347. This vulnerability allows remote attackers to obtain sensitive application (data of connected clients).

Buffer over-read vulnerability in Contiki-NG tinyDTLS through master branch 53a0d97 allows attackers obtain sensitive information via crafted input to dtlsccmdecryptmessage().

An assertion failure discovered in in checkcertificaterequest() in Contiki-NG tinyDTLS through master branch 53a0d97 allows attackers to cause a denial of service.

An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. An infinite loop bug exists during the handling of a ClientHello handshake message. This bug allows remote attackers to cause a denial of service by sending a malformed ClientHello handshake message with an odd length of cipher suites, which triggers an infinite loop (consuming all resources) and a buffer over-read that can disclose sensitive information.

An issue was discovered in Contiki-NG tinyDTLS through 2018-08-30. One incorrect handshake could complete with different epoch numbers in the packets ClientHello, Clientkeyexchange, and Changecipherspec, which may cause denial of service.

An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers mishandle the early use of a large epoch number. This vulnerability allows remote attackers to cause a denial of service and false-positive packet drops.

Buffer over-read vulnerability in the dtlssha256update function in Contiki-NG tinyDTLS through master branch 53a0d97 allows remote attackers to cause a denial of service via crafted data packet.

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. An attacker can trigger out-of-bounds reads in the RPL-Lite implementation of the RPL protocol in the Contiki-NG operating system. This vulnerability is caused by insufficient control of the lengths for DIO and DAO messages, in particular when they contain RPL sub-option headers. The problem has been patched in Contiki-NG 4.9. Users are advised to upgrade. Users unable to upgrade should manually apply the code changes in PR #2484.

Contiki-NG is an open-source, cross-platform operating system for IoT devices. In affected versions it is possible to cause a buffer overflow when copying an IPv6 address prefix in the RPL-Classic implementation in Contiki-NG. In order to trigger the vulnerability, the Contiki-NG system must have joined an RPL DODAG. After that, an attacker can send a DAO packet with a Target option that contains a prefix length larger than 128 bits. The problem was fixed after the release of Contiki-NG 4.7. Users unable to upgrade may apply the patch in Contiki-NG PR #1615.

Contiki-NG is an open-source, cross-platform operating system for IoT devices. Because of insufficient validation of IPv6 neighbor discovery options in Contiki-NG, attackers can send neighbor solicitation packets that trigger an out-of-bounds read. The problem exists in the module os/net/ipv6/uip-nd6.c, where memory read operations from the main packet buffer, <code>uipbuf</code>, are not checked if they go out of bounds. In particular, this problem can occur when attempting to read the 2-byte option header and the Source Link-Layer Address Option (SLLAO). This attack requires ipv6 be enabled for the network. The problem has been patched in the develop branch of Contiki-NG. The upcoming 4.8 release of Contiki-NG will include the patch.Users unable to upgrade may apply the patch in Contiki-NG PR #1654.

Contiki-NG is an open-source, cross-platform operating system for IoT devices. In the RPL-Classic routing protocol implementation in the Contiki-NG operating system, an incoming DODAG Information Option (DIO) control message can contain a prefix information option with a length parameter. The value of the length parameter is not validated, however, and it is possible to cause a buffer overflow when copying the prefix in the setipfromprefix function. This vulnerability affects anyone running a Contiki-NG version prior to 4.7 that can receive RPL DIO messages from external parties. To obtain a patched version, users should upgrade to Contiki-NG 4.7 or later. There are no workarounds for this issue.

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. The low-power IPv6 network stack of Contiki-NG has a buffer module (os/net/ipv6/uipbuf.c) that processes IPv6 extension headers in incoming data packets. As part of this processing, the function uipbufgetnextheader casts a pointer to a uipexthdr structure into the packet buffer at different offsets where extension headers are expected to be found, and then reads from this structure. Because of a lack of bounds checking, the casting can be done so that the structure extends beyond the packet's end. Hence, with a carefully crafted packet, it is possible to cause the Contiki-NG system to read data outside the packet buffer. A patch that fixes the vulnerability is included in Contiki-NG 4.8.

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. The 6LoWPAN implementation in Contiki-NG may cast a UDP header structure at a certain offset in a packet buffer. The code does not check whether the packet buffer is large enough to fit a full UDP header structure from the offset where the casting is made. Hence, it is possible to cause an out-of-bounds read beyond the packet buffer. The problem affects anyone running devices with Contiki-NG versions previous to 4.8, and which may receive 6LoWPAN packets from external parties. The problem has been patched in Contiki-NG version 4.8.

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. The 6LoWPAN implementation in the Contiki-NG operating system (file os/net/ipv6/sicslowpan.c) contains an input function that processes incoming packets and copies them into a packet buffer. Because of a missing length check in the input function, it is possible to write outside the packet buffer's boundary. The vulnerability can be exploited by anyone who has the possibility to send 6LoWPAN packets to a Contiki-NG system. In particular, the vulnerability is exposed when sending either of two types of 6LoWPAN packets: an unfragmented packet or the first fragment of a fragmented packet. If the packet is sufficiently large, a subsequent memory copy will cause an out-of-bounds write with data supplied by the attacker.

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. Versions prior to 4.9 contain a NULL Pointer Dereference in BLE L2CAP module. The Contiki-NG operating system for IoT devices contains a Bluetooth Low Energy stack. An attacker can inject a packet in this stack, which causes the implementation to dereference a NULL pointer and triggers undefined behavior. More specifically, while processing the L2CAP protocol, the implementation maps an incoming channel ID to its metadata structure. In this structure, state information regarding credits is managed through calls to the function inputl2capcredit in the module os/net/mac/ble/ble-l2cap.c. Unfortunately, the inputl2capcredit function does not check that the metadata corresponding to the user-supplied channel ID actually exists, which can lead to the channel variable being set to NULL before a pointer dereferencing operation is performed. The vulnerability has been patched in the "develop" branch of Contiki-NG, and will be included in release 4.9. Users can apply the patch in Contiki-NG pull request #2253 as a workaround until the new package is released.

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. Versions prior to and including 4.8 are vulnerable to an out-of-bounds write that can occur in the BLE-L2CAP module. The Bluetooth Low Energy - Logical Link Control and Adaptation Layer Protocol (BLE-L2CAP) module handles fragmentation of packets up the configured MTU size. When fragments are reassembled, they are stored in a packet buffer of a configurable size, but there is no check to verify that the packet buffer is large enough to hold the reassembled packet. In Contiki-NG's default configuration, it is possible that an out-of-bounds write of up to 1152 bytes occurs. The vulnerability has been patched in the "develop" branch of Contiki-NG, and will be included in release 4.9. The problem can be fixed by applying the patch in Contiki-NG pull request #2254 prior to the release of version 4.9.

Contiki-NG is an open-source, cross-platform operating system for internet of things (IoT) devices. In versions 4.8 and prior, an out-of-bounds write can occur in the BLE L2CAP module of the Contiki-NG operating system. The network stack of Contiki-NG uses a global buffer (packetbuf) for processing of packets, with the size of PACKETBUFSIZE. In particular, when using the BLE L2CAP module with the default configuration, the PACKETBUFSIZE value becomes larger then the actual size of the packetbuf. When large packets are processed by the L2CAP module, a buffer overflow can therefore occur when copying the packet data to the packetbuf. The vulnerability has been patched in the "develop" branch of Contiki-NG, and will be included in release 4.9. The problem can be worked around by applying the patch manually.

Contiki-NG is an operating system for Internet of Things devices. An off-by-one error can be triggered in the Antelope database management system in the Contiki-NG operating system in versions 4.8 and prior. The problem exists in the Contiki File System (CFS) backend for the storage of data (file os/storage/antelope/storage-cfs.c). In the functions storagegetindex and storageputindex, a buffer for merging two strings is allocated with one byte less than the maximum size of the merged strings, causing subsequent function calls to the cfsopen function to read from memory beyond the buffer size. The vulnerability has been patched in the "develop" branch of Contiki-NG, and is expected to be included in the next release. As a workaround, the problem can be fixed by applying the patch in Contiki-NG pull request #2425.

The Contiki-NG operating system versions 4.8 and prior can be triggered to dereference a NULL pointer in the message handling code for IPv6 router solicitiations. Contiki-NG contains an implementation of IPv6 Neighbor Discovery (ND) in the module os/net/ipv6/uip-nd6.c. The ND protocol includes a message type called Router Solicitation (RS), which is used to locate routers and update their address information via the SLLAO (Source Link-Layer Address Option). If the indicated source address changes, a given neighbor entry is set to the STALE state.

The message handler does not check for RS messages with an SLLAO that indicates a link-layer address change that a neighbor entry can actually be created for the indicated address. The resulting pointer is used without a check, leading to the dereference of a NULL pointer of type uipds6nbrt.

The problem has been patched in the develop branch of Contiki-NG, and will be included in the upcoming 4.9 release. As a workaround, users can apply Contiki-NG pull request #2271 to patch the problem directly.

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. An out-of-bounds read can be caused by an incoming DIO message when using the RPL-Lite implementation in the Contiki-NG operating system. More specifically, the prefix information of the DIO message contains a field that specifies the length of an IPv6 address prefix. The value of this field is not validated, which means that an attacker can set a value that is longer than the maximum prefix length. Subsequently, a memcmp function call that compares different prefixes can be called with a length argument that surpasses the boundary of the array allocated for the prefix, causing an out-of-bounds read. The problem has been patched in the "develop" branch of Contiki-NG, and is expected to be included in the next release. Users are advised to update as soon as they are able to or to manually apply the changes in Contiki-NG pull request #2721.

Contiki-NG is an open-source, cross-platform operating system for Next-Generation IoT devices. An out-of-bounds write exists in the driver for IEEE 802.15.4 radios on nRF platforms in the Contiki-NG operating system. The problem is triggered when parsing radio frames in the readframe function in the arch/cpu/nrf/net/nrf-ieee-driver-arch.c module. More specifically, the readframe function performs an incomplete validation of the payload length of the packet, which is a value that can be set by an external party that sends radio packets to a Contiki-NG system. Although the value is validated to be in the range of the MTU length, it is not validated to fit into the given buffer into which the packet will be copied. The problem has been patched in the "develop" branch of Contiki-NG and is expected to be included in subsequent releases. Users are advised to update their develop branch or to update to a subsequent release when available. Users unable to upgrade should consider manually applying the changes in PR #2741.

Contiki-NG is an open-source, cross-platform operating system for IoT devices. An out-of-bounds read of 1 byte can be triggered when sending a packet to a device running the Contiki-NG operating system with SNMP enabled. The SNMP module is disabled in the default Contiki-NG configuration. The vulnerability exists in the os/net/app-layer/snmp/snmp-ber.c module, where the function snmpberdecodestringlenbuffer decodes the string length from a received SNMP packet. In one place, one byte is read from the buffer, without checking that the buffer has another byte available, leading to a possible out-of-bounds read. The problem has been patched in Contiki-NG pull request #2936. It will be included in the next release of Contiki-NG. Users are advised to apply the patch manually or to wait for the next release. A workaround is to disable the SNMP module in the Contiki-NG build configuration.

Contiki-NG is an open-source, cross-platform operating system for IoT devices. An out-of-bounds read of 1 byte can be triggered when sending a packet to a device running the Contiki-NG operating system with SNMP enabled. The SNMP module is disabled in the default Contiki-NG configuration. The vulnerability exists in the os/net/app-layer/snmp/snmp-message.c module, where the snmpmessagedecode function fails to check the boundary of the message buffer when reading a byte from it immediately after decoding an object identifier (OID). The problem has been patched in Contiki-NG pull request 2937. It will be included in the next release of Contiki-NG. Users are advised to either apply the patch manually or to wait for the next release. A workaround is to disable the SNMP module in the Contiki-NG build configuration.

Contiki-NG is an open-source, cross-platform operating system for IoT devices. An unaligned memory access can be triggered in the two RPL implementations of the Contiki-NG operating system. The problem can occur when either one of these RPL implementations is enabled and connected to an RPL instance. If an IPv6 packet containing an odd number of padded bytes before the RPL option, it can cause the rplextheaderhbhupdate function to read a 16-bit integer from an odd address. The impact of this unaligned read is architecture-dependent, but can potentially cause the system to crash. The problem has not been patched as of release 4.9, but will be included in the next release. One can apply the changes in Contiki-NG pull request #2962 to patch the system or wait for the next release.