PT-2026-24697 · Emqx+2 · Nanomq

Fuzz0X · Published 2026-03-11 · Updated 2026-03-11 · CVE-2026-21888

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

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

Name of the Vulnerable Software and Affected Versions NanoMQ versions prior to 0.24.6

Description NanoMQ MQTT Broker is an all-around Edge Messaging Platform. A flaw exists in the parsing of MQTT v5 Variable Byte Integers where the get var integer() function does not perform sufficient bounds checking when accepting 5-byte varints. This can reliably cause an out-of-bounds read and subsequent crash when the software is compiled with AddressSanitizer (ASan).

Recommendations Update to a version newer than 0.24.6.

Exploit

Fix

Out of bounds Read

Weakness Enumeration

CWE-125

Related Identifiers

CVE-2026-21888

GHSA-CGGC-6M7W-J7X5

Affected Products

Nanomq

References · 6

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/21xxx/CVE-2026-21888.json · Exploit
• https://github.com/nanomq/nanomq/security/advisories/GHSA-cggc-6m7w-j7x5 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2026-21888 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-21888 · Security Note
• https://github.com/nanomq/nanomq/issues/2192 · Note
• https://twitter.com/cyberbivash/status/2031773486306251133 · Twitter Post