CVE-2026-71279
Zigbee2MQTT External JS Extension Path Traversal Leading to Remote Code Execution
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.
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Zigbee2MQTT External JS Extension Path Traversal Leading to Remote Code Execution
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.
- Record
CVE-2026-71279- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-22
- Updated
- 2026-11-02
EUVDEUVD-2026-53364
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.
- Record
EUVD-2026-53364- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-77vh-g47p-vh46
Zigbee2MQTT's ExternalJSExtension.getFilePath() (lib/extension/externalJS.ts) joins a `name`...
Zigbee2MQTT's ExternalJSExtension.getFilePath() (lib/extension/externalJS.ts) joins a name 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. Because path.join() resolves ../ sequences, a name such as ../../tmp/evil.js escapes the intended extensions directory. 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. Requires the enable_external_js config option (off by default, but commonly enabled in legacy installs) and MQTT broker access, which is frequently unauthenticated in real deployments. The identical unsanitized getFilePath() is also used by the extension-removal handler, enabling arbitrary file deletion.
- Record
GHSA-77vh-g47p-vh46- CVSS 3.1
- 8.0 High
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-22
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-71279- CVSS 3.1
- 8.0 High
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-22
- Updated
- 2026-11-02
OSV
Zigbee2MQTT External JS Extension Path Traversal Leading to Remote Code Execution
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.
- Record
CVE-2026-71279- CVSS 3.1
- 8.0 High
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-22
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-71279 is a high vulnerability (CVSS 8.1) in Koenkk Zigbee2mqtt, published August 5, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.57%, the 47th percentile. No source names a fixed version.