CVE-2026-47275

low

Published 2026-07-20 · Modified 2026-07-20

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CVSS v3

2.6

CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:L

CVSS v4 NEW

—

not yet in upstream

VIR risk

2.6

Description

In nanomq versions 0.24.11 and earlier, a NULL pointer dereference in `nni_mqttv5_msg_decode_connect()` allows a malicious MQTT broker to crash any connecting NanoMQ MQTTv5 client (including bridge mode) with a single packet, causing remote denial of service via SIGSEGV. In `nni_mqttv5_msg_decode_connect()` (`mqtt_codec.c:1863`), the code iterates over CONNECT properties using variable `prop` when it should use `will_prop`. When a CONNECT packet has no connect-level properties (`prop == NULL`) but has will properties (`will_prop != NULL`), dereferencing `prop->next` causes SIGSEGV at address `0x38` (NULL + `offsetof(property, next)`). This affects both `nanomq_cli` and **NanoMQ bridge mode** (Core component), as both use the same `mqtt_client.c` receive path. This can lead to remote DoS if a malicious MQTT broker can crash the client process with a single 35-byte packet and persistent DoS if auto-reconnect causes infinite crash loop.

Predictions

Exploit likelihood

38%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

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References

CWEs

CWE-476

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.