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BREW-ESPHOME-CVE-2021-41104 (PYSEC-2021-351)

Vulnerability from osv_homebrew – Published: 2026-08-13 16:45 – Updated: 2026-09-09 23:53 – Source website
VLAI
Details

ESPHome is a system to control the ESP8266/ESP32. Anyone with web_server enabled and HTTP basic auth configured on version 2021.9.1 or older is vulnerable to an issue in which web_server allows over-the-air (OTA) updates without checking user defined basic auth username & password. This issue is patched in version 2021.9.2. As a workaround, one may disable or remove web_server.

References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "fix": "bump",
        "range_state": "fixed",
        "upstream_fixed_in": "2021.9.2"
      },
      "package": {
        "ecosystem": "Homebrew",
        "name": "esphome",
        "purl": "pkg:brew/esphome"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2026.7.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "confidence": "high",
    "source": "matched",
    "strategy": "git",
    "upstream_evidence": [
      {
        "ecosystem": "GIT",
        "key": "https://github.com/esphome/esphome",
        "name": "https://github.com/esphome/esphome",
        "strategy": "git",
        "subject_version": "2026.8.2"
      },
      {
        "ecosystem": "PyPI",
        "key": "pkg:pypi/esphome@2026.8.2",
        "name": "esphome",
        "strategy": "registry",
        "subject_version": "2026.8.2"
      }
    ]
  },
  "details": "ESPHome is a system to control the ESP8266/ESP32. Anyone with web_server enabled and HTTP basic auth configured on version 2021.9.1 or older is vulnerable to an issue in which `web_server` allows over-the-air (OTA) updates without checking user defined basic auth username \u0026 password. This issue is patched in version 2021.9.2. As a workaround, one may disable or remove `web_server`.",
  "id": "BREW-esphome-CVE-2021-41104",
  "modified": "2026-09-09T23:53:49Z",
  "published": "2026-08-13T16:45:08Z",
  "references": [
    {
      "type": "FIX",
      "url": "https://github.com/esphome/esphome/commit/2234f6aacf8cc653307fed80f3750317a82c4f83"
    },
    {
      "type": "WEB",
      "url": "https://github.com/esphome/esphome/pull/2409/commits/207cde1667d8c799a197b78ca8a5a14de8d5ca1e"
    },
    {
      "type": "WEB",
      "url": "https://github.com/esphome/esphome/releases/tag/2021.9.2"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/esphome/esphome/security/advisories/GHSA-48mj-p7x2-5jfm"
    }
  ],
  "schema_version": "1.7.3",
  "upstream": [
    "PYSEC-2021-351",
    "CVE-2021-41104",
    "GHSA-48mj-p7x2-5jfm"
  ]
}



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