CVE-2025-68699

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Source

https://cve.org/CVERecord?id=CVE-2025-68699

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-68699.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2025-68699

Aliases

GHSA-qv5f-c6v2-2f8h

Published

2026-02-04T19:25:12Z

Modified

2026-08-12T15:14:53Z

Severity

6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H CVSS Calculator

Summary

NanoMQ $share/ Subscription Validation and Forwarding Parsing Inconsistency: NULL Pointer Increment Causes Crash

Details

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In version 0.24.6, NanoMQ has a protocol parsing / forwarding inconsistency when handling shared subscriptions ($share/). A malformed SUBSCRIBE topic such as $share/ab (missing the second /) is not strictly validated during the subscription stage, so the invalid Topic Filter is stored into the subscription table. Later, when any PUBLISH matches this subscription, the broker send path (nmq_pipe_send_start_v4/v5) performs a second $share/ parsing using strchr() and increments the returned pointer without NULL checks. If the second strchr() returns NULL, sub_topic++ turns the pointer into an invalid address (e.g. 0x1). This invalid pointer is then passed into topic_filtern(), which triggers strlen() and crashes with SIGSEGV. The crash is stable and remotely triggerable. This issue has been patched in version 0.24.7.

Database specific

{
    "cna_assigner":  "GitHub_M",
    "cwe_ids":  [
        "CWE-476"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/68xxx/CVE-2025-68699.json"
}

References

Affected packages

Git / github.com/nanomq/nanomq

Affected ranges

Type

GIT

Repo

https://github.com/nanomq/nanomq

Events

Introduced

dc3a3136cd82d5c005b8cd26a65fe53beaaf0eb9

Fixed

89d68d678e7f841ae7baa45cba8d9bc7ddc9ef4b

Database specific

Show details

{
    "cpe":  "cpe:2.3:a:emqx:nanomq:0.24.6:*:*:*:*:*:*:*",
    "extracted_events":  [
        {
            "introduced":  "0.24.6"
        },
        {
            "last_affected":  "0.24.6"
        }
    ],
    "source":  [
        "CPE_STRING",
        "REFERENCES"
    ]
}

Affected versions

0.*

0.24.6

= 0.*

= 0.24.6

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-68699.json"

vanir_signatures

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        "id":  "CVE-2025-68699-65738b67",
        "signature_type":  "Function",
        "signature_version":  "v1",
        "source":  "https://github.com/nanomq/nanomq/commit/89d68d678e7f841ae7baa45cba8d9bc7ddc9ef4b",
        "target":  {
            "file":  "nanomq/sub_handler.c",
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vanir_signatures_modified

"2026-08-12T15:14:53Z"