CVE-2026-73863

NanoMQ is an MQTT broker. Prior to 0.24.14, NanoMQ's broker-side MQTT v5 nmq_subinfo_decode() function in nng/src/sp/protocol/mqtt/mqtt_parser.c reuses len_of_varint from the outer Properties Length while parsing each SUBSCRIPTION_IDENTIFIER. A remote client can send a SUBSCRIBE packet with a multi-byte Properties Length and repeated subscription identifiers, causing get_var_integer() to begin at an incorrect offset and read beyond the heap message buffer. The flaw is reachable through the broker receive path and can crash the broker, while the separately reported topic-option off-by-one occurs later and is not this vulnerability. This issue is fixed in version 0.24.14.

CVSS

No CVSS.

References

Link	Resource
https://github.com/nanomq/NanoNNG/commit/f888fe39d6691b253ff9aee598ce58bbe449ab6f
https://github.com/nanomq/NanoNNG/pull/1518
https://github.com/nanomq/nanomq/releases/tag/0.24.14
https://github.com/nanomq/nanomq/security/advisories/GHSA-pf97-vm7h-q84m
https://github.com/nanomq/nanomq/security/advisories/GHSA-pf97-vm7h-q84m

Configurations

No configuration.

History

24 Sep 2026, 21:18

Type	Values Removed	Values Added
References	~~() https://github.com/nanomq/nanomq/security/advisories/GHSA-pf97-vm7h-q84m -~~	() https://github.com/nanomq/nanomq/security/advisories/GHSA-pf97-vm7h-q84m -

18 Sep 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-18 17:17

Updated : 2026-09-24 21:18

NVD link : CVE-2026-73863

Mitre link : CVE-2026-73863

CVE.ORG link : CVE-2026-73863

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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