Quick answers
- Is CVE-2026-47276 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-47276 being exploited in the wild.
- How severe is CVE-2026-47276?
- Medium severity, with a CVSS score of 6.5, published 20 July 2026.
- Which products and versions are affected?
- EMQ NanoMQ <= 0.24.11.
- Is there a fix for CVE-2026-47276?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-47276 attacked?
- It is attacked over the network, in a hosted service.
- Am I affected by CVE-2026-47276?
- Check whether you run EMQ NanoMQ at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A NULL pointer dereference exists in the `properties_parse()` function within `rest_api.c` of NanoMQ. The vulnerability is triggered when the REST API endpoint `/api/v4/mqtt/publish` receives a JSON payload where the `user_properties` field is formatted as a JSON array rather than the expected JSON object. The code uses `cJSON_ArrayForEach` to iterate over the elements but fails to validate the JSON type; since array elements in cJSON do not have key names, `item->string` is NULL. A subsequent call to `strlen(item->string)` results in a segmentation fault (SIGSEGV), crashing the broker process. This attack requires network access and valid HTTP Basic Authentication credentials. The issue is resolved in version 0.24.14.
Affected products
- NanoMQ NanoMQ <= 0.24.11
Timeline
- 2026-07-08: advisory: GitHub Security Advisory published
- 2026-07-20: disclosed: NVD publication date