EMQX is a scalable and reliable MQTT broker for AI, IoT, IIoT, and connected vehicles. Prior to versions 5.8.11, 5.9.3, 5.10.4, 6.0.3, 6.1.2, and 6.2.1, the plugin-install REST API and dashboard upload accepted stale grants created with emqx ctl plugins allow because there was no five-minute grant lifetime or SHA-256 package binding. An attacker with a compromised dashboard administrator credential or API key with plugin-install permission who finds a stale allowed name and version can upload attacker-controlled bytes under the allowed .tar.gz filename through POST /api/v5/plugins/install or the dashboard plugin upload. The broker then installs and runs attacker-controlled Erlang code with the privileges of the EMQX process. This issue is fixed in versions 5.8.11, 5.9.3, 5.10.4, 6.0.3, 6.1.2, and 6.2.1.

An issue in EMQ NanoMQ v.0.24.9 allows a remote attacker to cause a denial of service via the nniqosdbset function in brokertcp.c component

A vulnerability has been found in EMQX up to 6.2.0. This affects an unknown function of the file apps/emqx/src/emqxpersistentsessionds.erl of the component QoS 2 PUBLISH Packet Handler. Such manipulation leads to race condition. The attack may be performed from remote. A high complexity level is associated with this attack. The exploitability is reported as difficult. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure.

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Versions prior to 0.24.11 have a remotely triggerable heap buffer overflow in the uriparamparse function of NanoMQ's REST API. The vulnerability occurs due to an off-by-one error when allocating memory for query parameter keys and values, allowing an attacker to write a null byte beyond the allocated buffer. This can be triggered via a crafted HTTP request. Version 0.24.11 patches the issue.

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Prior to version 0.24.10, in NanoMQ's webhookinproc.c, the hookworkcb() function processes nng messages by parsing the message body with cJSONParse(body). The body is obtained from nngmsgbody(msg), which is a binary buffer without a guaranteed null terminator. This leads to an out-of-bounds read (OOB read) as cJSONParse reads until it finds a \0, potentially accessing memory beyond the allocated buffer (e.g., nngmsg metadata or adjacent heap/stack). The issue is often masked by nng's allocation padding (extra 32 bytes of zeros for non-power-of-two sizes <1024 or non-aligned). The overflow is reliably triggered when the JSON payload length is a power-of-two >=1024 (no padding added). This issue has been patched in version 0.24.10.

A vulnerability exists in the packet parsing logic of CocoaMQTT that allows an attacker (or a compromised/malicious MQTT broker) to remotely crash the host iOS/macOS/tvOS application.

The vulnerability is located in Source/FramePublish.swift during the extraction of the Topic string from the incoming byte array.

When parsing the Variable Header of a PUBLISH frame, the library reads the first two bytes to determine the topicLength. It then adds this length to the current position (pos) and attempts to slice the byte array to extract the string:

swift if let data = NSString(bytes: UInt8]), length: Int(len), encoding: String.Encoding.utf8.rawValue) { topic = data as String }

If a packet is received where the Topic Length evaluates to 0 (e.g., 0x00 0x00), the len variable becomes 0, and pos evaluates to 2.

The slicing logic dynamically calculates bytes[2...(2-1)], which becomes bytes[2...1]. Swift's ClosedRange operator (...) requires the lower bound to be less than or equal to the upper bound. Because 2 is not less than 1, Swift detects an out-of-bounds access attempt and immediately triggers a runtime trap (Fatal error: Range requires lowerBound <= upperBound), crashing the host application.

If an attacker publishes this 4-byte malformed payload to a shared topic with the RETAIN flag set to true, the MQTT broker will persist the payload. Any time a vulnerable client connects and subscribes to that topic, the broker will automatically push the malformed packet. The app will instantly crash in the background before the user can even interact with it. This effectively "bricks" the mobile application (a persistent DoS) until the retained message is manually wiped from the broker database.

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In NanoMQ version 0.24.6, after enabling auth.httpauth (HTTP authentication), when a client connects to the broker using MQTT CONNECT without providing username/password, and the configuration params uses the placeholders %u / %P (e.g., username="%u", password="%P"), the HTTP request construction phase enters authhttp.c:setdata(). This results in calling strlen() on a NULL pointer, causing a SIGSEGV crash. This crash can be triggered remotely, resulting in a denial of service. This issue has been patched in version 0.24.7.

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Prior to version 0.24.8, NanoMQ’s MQTT-over-WebSocket transport can be crashed by sending an MQTT packet with a deliberately large Remaining Length in the fixed header while providing a much shorter actual payload. The code path copies Remaining Length bytes without verifying that the current receive buffer contains that many bytes, resulting in an out-of-bounds read (ASAN reports OOB / crash). This is remotely triggerable over the WebSocket listener. This issue has been patched in version 0.24.8.

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. MQTT v5 Variable Byte Integer parsing out-of-bounds: getvarinteger() accepts 5-byte varints without bounds checks; reliably triggers OOB read / crash when built with ASan. This affects 0.24.6 and earlier.

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In version 0.24.6, by generating a combined traffic pattern of high-frequency publishes and rapid reconnect/kick-out using the same ClientID and massive subscribe/unsubscribe jitter, it is possible to reliably trigger heap memory corruption in the Broker process, causing it to exit immediately with SIGABRT due to free(): invalid pointer. As of time of publication, no known patched versions are available.

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In version 0.24.6, NanoMQ has a protocol parsing / forwarding inconsistency when handling shared subscriptions ($share/). A malformed SUBSCRIBE topic such as $share/ab (missing the second /) is not strictly validated during the subscription stage, so the invalid Topic Filter is stored into the subscription table. Later, when any PUBLISH matches this subscription, the broker send path (nmqpipesendstartv4/v5) performs a second $share/ parsing using strchr() and increments the returned pointer without NULL checks. If the second strchr() returns NULL, subtopic++ turns the pointer into an invalid address (e.g. 0x1). This invalid pointer is then passed into topicfiltern(), which triggers strlen() and crashes with SIGSEGV. The crash is stable and remotely triggerable. This issue has been patched in version 0.24.7.

NanoMQ v0.22.7 is vulnerable to Denial of Service (DoS) due to improper resource throttling. A crafted sequence of requests causes the recv-q queue to saturate, leading to the rapid exhaustion of system file descriptors (FDs). This exhaustion triggers a process crash, rendering the broker unable to provide services.

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Versions prior to 0.24.5 have a Heap-Use-After-Free (UAF) vulnerability within the MQTT bridge client component (implemented via the underlying NanoNNG library). The vulnerability is triggered when NanoMQ acts as a bridge connecting to a remote MQTT broker. A malicious remote broker can trigger a crash (Denial of Service) or potential memory corruption by accepting the connection and immediately sending a malformed packet sequence. Version 0.34.5 contains a patch. The patch enforces stricter protocol adherence in the MQTT client SDK embedded in NanoMQ. Specifically, it ensures that CONNACK is always the first packet processed in the line. This prevents the state confusion that led to the Heap-Use-After-Free (UAF) when a malicious server sent a malformed packet sequence immediately after connection establishment. As a workaround, validate the remote broker before bridging.

NanoMQ MQTT Broker (NanoMQ) is an Edge Messaging Platform. Prior to version 0.24.2, there is a classical data racing issue about sub info list which could result in heap use after free crash. This issue has been patched in version 0.24.2.

NanoMQ is a messaging broker/bus for IoT Edge & SDV. Versions prior to 0.24.4 have a buffer overflow case while the PUBLISH packets trigger both shared subscription and vanila subscription. This is fixed in version 0.24.4. As a workaround, disable shared subscription.

NanoMQ v0.17.9 was discovered to contain a heap use-after-free vulnerability via the component subCtxhandle. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted SUBSCRIBE message.

An access control issue in NanoMQ v0.21.10 allows attackers to bypass security restrictions and access sensitive system topic messages using MQTT wildcard characters.

NanoMQ 0.17.5 was discovered to contain a segmentation fault via the component /nanomq/pubhandler.c. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted PUBLISH message.

NanoMQ v0.22.10 was discovered to contain a memory leak which allows attackers to cause a Denial of Service (DoS) via a crafted PUBLISH message.

A segmentation fault in NanoMQ v0.21.10 allows attackers to cause a Denial of Service (DoS) via crafted messages.

NanoMQ v0.22.10 was discovered to contain a heap overflow which allows attackers to cause a Denial of Service (DoS) via a crafted CONNECT message.

A vulnerability classified as problematic was found in emqx neuron up to 2.10.0. Affected by this vulnerability is an unknown functionality of the file /api/v2/schema of the component JSON File Handler. The manipulation leads to information disclosure. The attack can be launched remotely. The patch is named c9ce39747e0372aaa2157b2b56174914a12c06d8. It is recommended to apply a patch to fix this issue.

A vulnerability classified as critical has been found in emqx neuron up to 2.10.0. Affected is the function handleaddplugin in the library cmd.library of the file plugins/restful/pluginhandle.c. The manipulation leads to buffer overflow. It is possible to launch the attack remotely. It is recommended to apply a patch to fix this issue.

An invalid read size in Nanomq v0.21.9 allows attackers to cause a Denial of Service (DoS).

A heap-buffer-overflow vulnerability in the readbyte function in NanoMQ v.0.21.7 allows attackers to cause a denial of service via transmission of crafted hexstreams.

Null Pointer Dereference vulnerability in topicfiltern function in mqttparser.c in NanoMQ 0.21.7 allows attackers to cause a denial of service.

Buffer Overflow vulnerability in the getvarinteger function in mqttparser.c in NanoMQ 0.21.7 allows remote attackers to cause a denial of service via a series of specially crafted hexstreams.

nanomq 0.21.2 contains a Use-After-Free vulnerability in /nanomq/nng/src/core/socket.c.

An issue in the emqxsn plugin of EMQX v4.3.8 allows attackers to execute a directory traversal via uploading a crafted .txt file.

NanoMQ 0.17.5 has a one-byte heap-based buffer over-read in the connhandler function of mqttparser.c when it processes malformed messages.