Vulnerability-Lookup

GHSA-2VFR-CH7V-7754

Vulnerability from github – Published: 2026-05-11 18:31 – Updated: 2026-05-11 18:31

Details

In Meari IoT Cloud MQTT Broker deployments running EMQX 4.x, any authenticated low-privilege account can subscribe to global wildcard topics and receive telemetry from devices the user does not own. The broker enforces publish restrictions but does not enforce equivalent subscribe authorization at per-device scope.

Severity ?

7.7 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-33356"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-639"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-11T17:16:30Z",
    "severity": "HIGH"
  },
  "details": "In Meari IoT Cloud MQTT Broker deployments running EMQX 4.x, any authenticated low-privilege account can subscribe to global wildcard topics and receive telemetry from devices the user does not own. The broker enforces publish restrictions but does not enforce equivalent subscribe authorization at per-device scope.",
  "id": "GHSA-2vfr-ch7v-7754",
  "modified": "2026-05-11T18:31:45Z",
  "published": "2026-05-11T18:31:44Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33356"
    },
    {
      "type": "WEB",
      "url": "https://github.com/xn0tsa/nobody-puts-baby-in-a-corner"
    },
    {
      "type": "WEB",
      "url": "https://www.runzero.com/advisories/meari-mqtt-broker-missing-per-device-subscribe-acl-cve-2026-33356"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-33356 (GCVE-0-2026-33356)

Vulnerability from cvelistv5 – Published: 2026-05-11 16:02 – Updated: 2026-05-11 18:18

Title

Meari MQTT broker missing per-device subscribe ACL

Summary

Severity ?

7.7 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

CWE

CWE-639 - Authorization Bypass Through User-Controlled Key

Assigner

runZero

References

2 references

URL	Tags
https://github.com/xn0tsa/nobody-puts-baby-in-a-corner	technical-description
https://www.runzero.com/advisories/meari-mqtt-bro…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
Meari	IoT Cloud MQTT Broker EMQX	Affected: 4.x (custom)

Date Public ?

2026-05-11 16:00

Credits

Sammy Azdoufal Tod Beardsley of runZero, Inc.

Show details on NVD website

JSON

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  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-33356",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-11T18:18:36.704517Z",
                "version": "2.0.3"
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          "dateUpdated": "2026-05-11T18:18:45.410Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "IoT Cloud MQTT Broker EMQX",
          "vendor": "Meari",
          "versions": [
            {
              "status": "affected",
              "version": "4.x",
              "versionType": "custom"
            }
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          "type": "finder",
          "value": "Sammy Azdoufal"
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        {
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          "type": "coordinator",
          "value": "Tod Beardsley of runZero, Inc."
        }
      ],
      "datePublic": "2026-05-11T16:00:00.000Z",
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        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.7,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
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        "dateUpdated": "2026-05-11T16:02:14.046Z",
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          ],
          "url": "https://www.runzero.com/advisories/meari-mqtt-broker-missing-per-device-subscribe-acl-cve-2026-33356/"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "Meari MQTT broker missing per-device subscribe ACL",
      "x_generator": {
        "engine": "Vulnogram 1.0.2"
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  },
  "cveMetadata": {
    "assignerOrgId": "44488dab-36db-4358-99f9-bc116477f914",
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    "cveId": "CVE-2026-33356",
    "datePublished": "2026-05-11T16:02:14.046Z",
    "dateReserved": "2026-03-19T00:27:05.986Z",
    "dateUpdated": "2026-05-11T18:18:45.410Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-2VFR-CH7V-7754

CVE-2026-33356 (GCVE-0-2026-33356)

Tags

Sightings

Nomenclature