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

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In 0.24.8 and earlier, quicstreamrecv can dereference a null substream pointer when a substream is in reopen state. The code finishes the AIO with error but does not return before locking c->mtx.

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.

In Meari IoT Cloud MQTT Broker deployments running EMQX 4.x, any authenticated low-privilege account can subscribe to global wildcard topics and receive telemetry from devices the user does not own. The broker enforces publish restrictions but does not enforce equivalent subscribe authorization at per-device scope.

A vulnerability was found in EMQ EMQX Enterprise up to 6.1.0. The impacted element is an unknown function of the component Session Handling. The manipulation results in improper authorization. It is possible to launch the attack remotely. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.

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.

In EMQX before 5.8.6, administrators can install arbitrary novel plugins via the Dashboard web interface. NOTE: the Supplier's position is that this is the intended behavior; however, 5.8.6 adds a defense-in-depth feature in which a plugin's acceptability (for later Dashboard installation) is set by the "emqx ctl plugins allow" CLI command.