Vulnerability Description
NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Prior to version 0.24.10, in NanoMQ's webhook_inproc.c, the hook_work_cb() function processes nng messages by parsing the message body with cJSON_Parse(body). The body is obtained from nng_msg_body(msg), which is a binary buffer without a guaranteed null terminator. This leads to an out-of-bounds read (OOB read) as cJSON_Parse reads until it finds a \0, potentially accessing memory beyond the allocated buffer (e.g., nng_msg 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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Emqx | Nanomq | < 0.24.10 |
Related Weaknesses (CWE)
References
- https://github.com/nanomq/nanomq/commit/9499a4b2c47998a6aadb69238c18b9e6771b1691Patch
- https://github.com/nanomq/nanomq/releases/tag/0.24.10ProductRelease Notes
- https://github.com/nanomq/nanomq/security/advisories/GHSA-8p57-jxj9-3qq3ExploitMitigationVendor Advisory
FAQ
What is CVE-2026-34608?
CVE-2026-34608 is a vulnerability with a CVSS score of 4.9 (MEDIUM). NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Prior to version 0.24.10, in NanoMQ's webhook_inproc.c, the hook_work_cb() function processes nng messages by parsing the message ...
How severe is CVE-2026-34608?
CVE-2026-34608 has been rated MEDIUM with a CVSS base score of 4.9/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-34608?
Check the references section above for vendor advisories and patch information. Affected products include: Emqx Nanomq.