What is CVE-2025-59947?

CVE-2025-59947 is a critical-severity vulnerability in Emqx Nanomq, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.0/10. Published 2025-12-15.

How severe is CVE-2025-59947?

Critical severity. CVSS v3 base score is 9.0 out of 10.

Buffer overflow in Emqx Nanomq

CVE-2025-59947

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…

Vulnerability class: Buffer Overflow

EPSS: 0.003 (19.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H.

Affected products

Emqx Nanomq
Nanomq — versions < 0.24.4

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
security-advisories@github.com (Patch, x_refsource_MISC, Issue Tracking)
security-advisories@github.com (Patch, x_refsource_MISC)

Frequently asked questions

What is CVE-2025-59947?: CVE-2025-59947 is a critical-severity vulnerability in Emqx Nanomq, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.0/10. Published 2025-12-15.
How severe is CVE-2025-59947?: Critical severity. CVSS v3 base score is 9.0 out of 10.