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

Vulnerability from osv_homebrew – Published: 2026-08-13 16:45 – Updated: 2026-10-02 09:09 – 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": "2026.9.1"
      },
      {
        "ecosystem": "PyPI",
        "key": "pkg:pypi/esphome@2026.9.1",
        "name": "esphome",
        "strategy": "registry",
        "subject_version": "2026.9.1"
      }
    ]
  },
  "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": "2026-10-02T09:09:18Z",
  "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"
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    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.