CVE-2024-27081: Esphome Remote Code Execution Vulnerability

HIGH
Advisory Identifier: GHSA-8p25-3q46-8q2p
CVSS 7.2
CWE-22
Published
Advisory Summary

CVE-2024-27081 is a HIGH (CVSS 7.2) remote code execution vulnerability (CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')) affecting Esphome libraries in the PyPI ecosystem. The issue involves esphome vulnerable to remote code execution via arbitrary file write. Remediation is available by upgrading affected packages to version 2024.2.1.

CVE-2024-27081 at a Glance

CVE Identifier CVE-2024-27081
GHSA Identifier GHSA-8p25-3q46-8q2p
Severity HIGH
CVSS v3.1 Base Score 7.2
CWE Classification CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Affected Product Esphome
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 7.2

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required High (PR:H)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2024-27081

To remediate this vulnerability, upgrade all affected Esphome dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

esphome fixed: 2024.2.1
pip install esphome>=2024.2.1
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

pip show esphome

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2024-27081, inspect your installed packages using pip:

pip show esphome

Analyze the terminal output to locate any version of Esphome in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2024.2.1), your application is affected.

Note: The pip show esphome command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'), where the product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. In Esphome, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary Security misconfiguration in edit configuration file API in dashboard component of ESPHome version 2023.12.9 (command line installation) allows authenticated remote attackers to read and write arbitrary files under the configuration directory rendering remote code execution possible. ### Details It is possible to abuse this path traversal vulnerability both in command line installation and Home Assistant add-on, but it is possible to read and write files only under the configuration directory. The vulnerability is present and exploitable in the command line installation, but it was not possible to confirm an impact in the home assistant add-on version. ### PoC <img width="482" alt="/edit?configuration=/config/.esphome/esphome.json" src="https://github.com/esphome/esphome/assets/115887876/d2da3180-976e-4bed-b4b9-35ac960a7fb4"> <br/> <img width="344" alt="/edit?configuration=/config/.esphome/build/test01/src/main.cpp (firmware for board named test01)" src="https://github.com/esphome/esphome/assets/115887876/707fb6d7-d4a8-461e-bbb7-05382471e925"> <br/> <img width="482" alt="RCE payload POST request on /edit?configuration=.esphome/platformio/packages/tool-esptoolpy/esptool.py" src="https://github.com/esphome/esphome/assets/115887876/c6cb28d8-352d-4fea-b77a-705f63be94e3"> <br/> <img width="482" alt="Arbitrary code execution during ESP board flashing" src="https://github.com/esphome/esphome/assets/115887876/5eb0f14c-ceb2-4b15-8898-c02c610763d1"> ### Impact The issue gives read and write access to files under the configuration directory and allows malicious users to write arbitrary code in python scripts executed during the compilation and flashing of firmwares for ESP boards. If chained with GHSA-9p43-hj5j-96h5 and GHSA-5925-88xh-6h99, this issue could allow an unauthenticated remote user to gain remote code execution on the machine hosting the dashboard. It also allows accessing sensitive information such as esphome.json and board firmware source code allowing a user to modify the board firmware, and leaking secrets such as: WiFi network credentials, fallback hotspot WiFi credentials, OTA component authentication password and API encryption key. ### Credits Spike Reply Cybersecurity Team

CVE-2024-27081 Affected Esphome Versions

1 component(s)
Fixed Versions:
2024.2.1
Product / Package Ecosystem Affected Versions Fixed Version
esphome
PyPI
≥ 2023.12.9
< 2024.2.1
All 1 versions
2023.12.9
2024.2.1

References

Frequently Asked Questions

What is CVE-2024-27081?
CVE-2024-27081 is a security vulnerability in Esphome involving ESPHome vulnerable to remote code execution via arbitrary file write under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal').
Which Esphome versions are affected?
Affected versions include releases prior to 2024.2.1 across affected packages: esphome.
What version fixes CVE-2024-27081?
Upgrading to 2024.2.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is esphome affected?
Yes, esphome is affected in releases prior to 2024.2.1. Upgrade your dependency to 2024.2.1 or later.
What is the CVSS score of CVE-2024-27081?
CVE-2024-27081 has a CVSS v3.1 base score of 7.2 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2024-27081?
CVE-2024-27081 is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') (The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.).
How can I check PyPI dependencies for CVE-2024-27081?
Run the dependency tree command: 'pip show esphome'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-8p25-3q46-8q2p",
  "modified" : "2025-02-07T20:44:54Z",
  "published" : "2024-03-01T20:09:19Z",
  "aliases" : [ "CVE-2024-27081" ],
  "summary" : "ESPHome vulnerable to remote code execution via arbitrary file write",
  "details" : "### Summary\nSecurity misconfiguration in edit configuration file API in dashboard component of ESPHome version 2023.12.9 (command line installation) allows authenticated remote attackers to read and write arbitrary files under the configuration directory rendering remote code execution possible.\n\n### Details\nIt is possible to abuse this path traversal vulnerability both in command line installation and Home Assistant add-on, but it is possible to read and write files only under the configuration directory. \n\nThe vulnerability is present and exploitable in the command line installation, but it was not possible to confirm an impact in the home assistant add-on version.\n\n### PoC\n<img width=\"482\" alt=\"/edit?configuration=/config/.esphome/esphome.json\" src=\"https://github.com/esphome/esphome/assets/115887876/d2da3180-976e-4bed-b4b9-35ac960a7fb4\">\n<br/>\n\n<img width=\"344\" alt=\"/edit?configuration=/config/.esphome/build/test01/src/main.cpp (firmware for board named test01)\" src=\"https://github.com/esphome/esphome/assets/115887876/707fb6d7-d4a8-461e-bbb7-05382471e925\">\n<br/>\n\n<img width=\"482\" alt=\"RCE payload POST request on /edit?configuration=.esphome/platformio/packages/tool-esptoolpy/esptool.py\" src=\"https://github.com/esphome/esphome/assets/115887876/c6cb28d8-352d-4fea-b77a-705f63be94e3\">\n<br/>\n\n<img width=\"482\" alt=\"Arbitrary code execution during ESP board flashing\" src=\"https://github.com/esphome/esphome/assets/115887876/5eb0f14c-ceb2-4b15-8898-c02c610763d1\">\n\n\n### Impact\nThe issue gives read and write access to files under the configuration directory and allows malicious users to write arbitrary code in python scripts executed during the compilation and flashing of firmwares for ESP boards. \n\nIf chained with GHSA-9p43-hj5j-96h5 and GHSA-5925-88xh-6h99, this issue could allow an unauthenticated remote user to gain remote code execution on the machine hosting the dashboard.\n\nIt also allows accessing sensitive information such as esphome.json and board firmware source code allowing a user to modify the board firmware, and leaking secrets such as: WiFi network credentials, fallback hotspot WiFi credentials, OTA component authentication password and API encryption key.\n\n### Credits\nSpike Reply Cybersecurity Team",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "esphome"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2023.12.9"
      }, {
        "fixed" : "2024.2.1"
      } ]
    } ],
    "versions" : [ "2023.12.9" ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/esphome/esphome/security/advisories/GHSA-8p25-3q46-8q2p"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2024-27081"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/esphome/esphome/commit/d814ed1d4adc71fde47c4df41215bee449884513"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/esphome/esphome"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-22" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2024-03-01T20:09:19Z",
    "nvd_published_at" : "2024-02-26T17:15:10Z"
  }
}