GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2026-71279 (GCVE-0-2026-71279)

Vulnerability from cvelistv5 – Published: 2026-08-05 12:26 – Updated: 2026-08-10 11:47
VLAI
Title
Zigbee2MQTT External JS Extension Path Traversal Leading to Remote Code Execution
Summary
Zigbee2MQTT's ExternalJSExtension.getFilePath (lib/extension/externalJS.ts) joins a parameter received via an MQTT message (topic zigbee2mqtt/bridge/request/extension/save) into the extensions base path using path.join(basePath, name) with no sanitization. The extension handler only validates that the name ends in .js/.mjs/.cjs, writes the file, and then dynamically imports it via Node.js import, achieving remote code execution.
Severity
8.1 (High)
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-05 15:55 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Koenkk zigbee2mqtt Affected: 0 , ≤ 2.12.0 (semver)
guessed Create a notification for this product.
Date Public
2026-08-05 12:26
Credits
Alibek Baxtiyorov
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-71279",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-05T15:55:04.507481Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-05T15:55:11.665Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "zigbee2mqtt",
          "programFiles": [
            "lib/extension/externalJS.ts"
          ],
          "vendor": "Koenkk",
          "versions": [
            {
              "lessThanOrEqual": "2.12.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Alibek Baxtiyorov"
        }
      ],
      "datePublic": "2026-08-05T12:26:25.594Z",
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eZigbee2MQTT\u0027s ExternalJSExtension.getFilePath (lib/extension/externalJS.ts) joins a parameter received via an MQTT message (topic zigbee2mqtt/bridge/request/extension/save) into the extensions base path using path.join(basePath, name) with no sanitization. The extension handler only validates that the name ends in .js/.mjs/.cjs, writes the file, and then dynamically imports it via Node.js import, achieving remote code execution.\u003c/p\u003e"
            }
          ],
          "value": "Zigbee2MQTT\u0027s ExternalJSExtension.getFilePath (lib/extension/externalJS.ts) joins a parameter received via an MQTT message (topic zigbee2mqtt/bridge/request/extension/save) into the extensions base path using path.join(basePath, name) with no sanitization. The extension handler only validates that the name ends in .js/.mjs/.cjs, writes the file, and then dynamically imports it via Node.js import, achieving remote code execution."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "ADJACENT_NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 8.1,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-22",
              "description": "CWE-22",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-10T11:47:00.480Z",
        "orgId": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
        "shortName": "TuranSec"
      },
      "references": [
        {
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://github.com/Koenkk/zigbee2mqtt"
        },
        {
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://github.com/Koenkk/zigbee2mqtt/blob/master/lib/extension/externalJS.ts"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "Zigbee2MQTT External JS Extension Path Traversal Leading to Remote Code Execution"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
    "assignerShortName": "TuranSec",
    "cveId": "CVE-2026-71279",
    "datePublished": "2026-08-05T12:26:25.594Z",
    "dateReserved": "2026-08-05T12:23:34.967Z",
    "dateUpdated": "2026-08-10T11:47:00.480Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-71279",
      "date": "2026-09-19",
      "epss": "0.00363",
      "percentile": "0.30159"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "zigbee2mqtt",
                "programFiles": [
                  "lib/extension/externalJS.ts"
                ],
                "vendor": "Koenkk",
                "versions": [
                  {
                    "lessThanOrEqual": "2.12.0",
                    "status": "affected",
                    "version": "0",
                    "versionType": "semver"
                  }
                ]
              }
            ],
            "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "Zigbee2MQTT\u0027s ExternalJSExtension.getFilePath (lib/extension/externalJS.ts) joins a parameter received via an MQTT message (topic zigbee2mqtt/bridge/request/extension/save) into the extensions base path using path.join(basePath, name) with no sanitization. The extension handler only validates that the name ends in .js/.mjs/.cjs, writes the file, and then dynamically imports it via Node.js import, achieving remote code execution."
          }
        ],
        "id": "CVE-2026-71279",
        "lastModified": "2026-08-26T17:13:24.800",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "ADJACENT_NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 8.0,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 2.1,
              "impactScore": 5.9,
              "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
              "type": "Secondary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2026-71279",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-05T15:55:04.507481Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-08-05T13:24:52.437",
        "references": [
          {
            "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
            "url": "https://github.com/Koenkk/zigbee2mqtt"
          },
          {
            "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
            "url": "https://github.com/Koenkk/zigbee2mqtt/blob/master/lib/extension/externalJS.ts"
          }
        ],
        "sourceIdentifier": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
        "vulnStatus": "Deferred",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-22"
              }
            ],
            "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
            "type": "Secondary"
          }
        ]
      }
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2026-71279",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "total"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-08-05T15:55:04.507481Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-08-05T15:55:07.728Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unaffected",
              "product": "zigbee2mqtt",
              "programFiles": [
                "lib/extension/externalJS.ts"
              ],
              "vendor": "Koenkk",
              "versions": [
                {
                  "lessThanOrEqual": "2.12.0",
                  "status": "affected",
                  "version": "0",
                  "versionType": "semver"
                }
              ]
            }
          ],
          "credits": [
            {
              "lang": "en",
              "type": "finder",
              "value": "Alibek Baxtiyorov"
            }
          ],
          "datePublic": "2026-08-05T12:26:25.594Z",
          "descriptions": [
            {
              "lang": "en",
              "supportingMedia": [
                {
                  "base64": false,
                  "type": "text/html",
                  "value": "\u003cp\u003eZigbee2MQTT\u0027s ExternalJSExtension.getFilePath (lib/extension/externalJS.ts) joins a parameter received via an MQTT message (topic zigbee2mqtt/bridge/request/extension/save) into the extensions base path using path.join(basePath, name) with no sanitization. The extension handler only validates that the name ends in .js/.mjs/.cjs, writes the file, and then dynamically imports it via Node.js import, achieving remote code execution.\u003c/p\u003e"
                }
              ],
              "value": "Zigbee2MQTT\u0027s ExternalJSExtension.getFilePath (lib/extension/externalJS.ts) joins a parameter received via an MQTT message (topic zigbee2mqtt/bridge/request/extension/save) into the extensions base path using path.join(basePath, name) with no sanitization. The extension handler only validates that the name ends in .js/.mjs/.cjs, writes the file, and then dynamically imports it via Node.js import, achieving remote code execution."
            }
          ],
          "metrics": [
            {
              "cvssV3_1": {
                "attackComplexity": "LOW",
                "attackVector": "ADJACENT_NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 8.1,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              }
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "cweId": "CWE-22",
                  "description": "CWE-22",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-08-10T11:47:00.480Z",
            "orgId": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
            "shortName": "TuranSec"
          },
          "references": [
            {
              "tags": [
                "third-party-advisory"
              ],
              "url": "https://github.com/Koenkk/zigbee2mqtt"
            },
            {
              "tags": [
                "third-party-advisory"
              ],
              "url": "https://github.com/Koenkk/zigbee2mqtt/blob/master/lib/extension/externalJS.ts"
            }
          ],
          "source": {
            "discovery": "EXTERNAL"
          },
          "title": "Zigbee2MQTT External JS Extension Path Traversal Leading to Remote Code Execution"
        }
      },
      "cveMetadata": {
        "assignerOrgId": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
        "assignerShortName": "TuranSec",
        "cveId": "CVE-2026-71279",
        "datePublished": "2026-08-05T12:26:25.594Z",
        "dateReserved": "2026-08-05T12:23:34.967Z",
        "dateUpdated": "2026-08-10T11:47:00.480Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.