CVE-2026-73863

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Source
https://cve.org/CVERecord?id=CVE-2026-73863
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-73863.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-73863
Aliases
  • GHSA-pf97-vm7h-q84m
Published
2026-09-18T16:20:18Z
Modified
2026-09-20T14:13:56Z
Severity
  • 7.0 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:H CVSS Calculator
Summary
NanoMQ: Heap-Buffer-Overflow in `nmq_subinfo_decode()` During MQTT v5 SUBSCRIBE Parsing
Details

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.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-125"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/73xxx/CVE-2026-73863.json"
}
References

Affected packages

Git / github.com/nanomq/nanomq

Affected ranges

Type
GIT
Repo
https://github.com/nanomq/nanomq
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
16bdb38921e7bbeab887cf229c2eb145889dfa88
Database specific
Show details 
{
    "source": "REFERENCES"
}
Type
GIT
Repo
https://github.com/nanomq/nanonng
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
f888fe39d6691b253ff9aee598ce58bbe449ab6f
Database specific
Show details 
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "0.24.14"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

Affected versions

0.*
0.0.1
0.0.2
0.0.3
0.1.0
0.10.1
0.10.5
0.10.8
0.11.0
0.11.2
0.11.3
0.11.5
0.11.8
0.11.82
0.12.0
0.12.1
0.12.2
0.12.5
0.13
0.13.0
0.13.5
0.13.6
0.13.8
0.14.0
0.14.1
0.14.5
0.14.8
0.15.0
0.15.1
0.15.2
0.15.3
0.15.5
0.16.0
0.16.2
0.16.3
0.16.5
0.17.0
0.17.2
0.17.5
0.17.8
0.18.1
0.18.2
0.19.0
0.19.1
0.19.5
0.2.0
0.2.1
0.2.2
0.2.5
0.20.0
0.20.5
0.20.6
0.20.8
0.21
0.21.1
0.21.10
0.21.2
0.21.5
0.21.6
0.21.7
0.21.8
0.21.9
0.22.0
0.22.1
0.22.10
0.22.2
0.22.3
0.22.4
0.22.6
0.22.7
0.22.8
0.23.0
0.23.1
0.23.10
0.23.2
0.23.3
0.23.4
0.23.5
0.23.6
0.23.7
0.23.7-11
0.23.8
0.23.9
0.24.0
0.24.1
0.24.10
0.24.11
0.24.11-sdv
0.24.12
0.24.13
0.24.2
0.24.3
0.24.3-5
0.24.4
0.24.5
0.24.6
0.24.7
0.24.8
0.24.9
0.3.0
0.3.2
0.3.3
0.3.4
0.3.5
0.3.8
0.4.0
0.4.1
0.4.2
0.4.3
0.4.5
0.4.8
0.5.0
0.5.2
0.5.5
0.5.8
0.5.9
0.6.0
0.6.2
0.6.3
0.6.4
0.6.7rc
0.6.8
0.7.0
0.7.2
0.7.3
0.7.4
0.7.4rc
0.7.5
0.7.5rc
0.7.8
0.7.9
0.8.0
0.8.3
0.8.5
0.8.6log
0.9.0
0.9.2
0.9.5
0.9.7

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-73863.json"
vanir_signatures 
[
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "77509335656239371113854997065539380849",
                "190729711231283871155441871641728927427",
                "228976448647505948214915489401682850940",
                "326568327721855343452730345885002467887",
                "269870189656849769321868917559742160824",
                "296206101973994187276197140470843593458",
                "246005441416754822632088318050137960443"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-73863-7ffed038",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/nanomq/nanonng/commit/f888fe39d6691b253ff9aee598ce58bbe449ab6f",
        "target": {
            "file": "src/sp/protocol/mqtt/mqtt_parser.c"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "15508866328687162543267351878097629872",
            "length": 1870
        },
        "id": "CVE-2026-73863-a2e61462",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/nanomq/nanonng/commit/f888fe39d6691b253ff9aee598ce58bbe449ab6f",
        "target": {
            "file": "src/sp/protocol/mqtt/mqtt_parser.c",
            "function": "nmq_subtopic_decode"
        }
    }
]
vanir_signatures_modified 
"2026-09-20T14:13:56Z"