CVE-2026-21888 (GCVE-0-2026-21888)

Vulnerability from cvelistv5 – Published: 2026-03-11 15:22 – Updated: 2026-03-11 15:35
VLAI
Title
MQTT v5 Variable Byte Integer parsing out-of-bounds: get_var_integer()
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-11 15:35 UTC
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7993 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
nanomq nanomq Affected: <= 0.24.6
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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