CVE-2026-21888 - Vulnerability Details - OpenCVE

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. MQTT v5 Variable Byte Integer parsing out-of-bounds: get_var_integer() accepts 5-byte varints without bounds checks; reliably triggers OOB read / crash when built with ASan. This affects 0.24.6 and earlier.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation poc

Automatable yes

Technical Impact partial

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://github.com/nanomq/nanomq/issues/2192
https://github.com/nanomq/nanomq/security/advisories/GHSA-cggc-6m7w-j7x5

History

Wed, 11 Mar 2026 16:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Wed, 11 Mar 2026 15:30:00 +0000

Type	Values Removed	Values Added
Description		NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. MQTT v5 Variable Byte Integer parsing out-of-bounds: get_var_integer() accepts 5-byte varints without bounds checks; reliably triggers OOB read / crash when built with ASan. This affects 0.24.6 and earlier.
Title		MQTT v5 Variable Byte Integer parsing out-of-bounds: get_var_integer()
Weaknesses		CWE-125
References		https://github.com/nanomq/nanomq/issues/2192 https://github.com/nanomq/nanomq/security/advisories/GHSA-cggc-6m7w-j7x5
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-03-11T15:22:32.463Z

Updated: 2026-03-11T15:35:36.678Z

Reserved: 2026-01-05T17:24:36.929Z

Link: CVE-2026-21888

Vulnrichment

Updated: 2026-03-11T15:35:27.865Z

NVD

Status : Received

Published: 2026-03-11T16:16:23.930

Modified: 2026-03-11T16:16:23.930

Link: CVE-2026-21888

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-125

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