Basic auth bypass in esphome
Impact
Anyone with web_server enabled and HTTP basic auth configured on 2021.9.1 or older
web_server allows OTA update without checking user defined basic auth username & password
Patches
Patch released in 2021.9.2
Workarounds
Disable/remove web_server
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | esphome | < 2021.9.2 | 2021.9.2 |
References
- https://github.com/esphome/esphome/commit/2234f6aacf8cc653307fed80f3750317a82c4f83
- https://github.com/esphome/esphome/pull/2409/commits/207cde1667d8c799a197b78ca8a5a14de8d5ca1e
- https://github.com/esphome/esphome/releases/tag/2021.9.2
- https://github.com/esphome/esphome/security/advisories/GHSA-48mj-p7x2-5jfm
- https://nvd.nist.gov/vuln/detail/CVE-2021-41104
- https://github.com/esphome/esphome/pull/2409
- https://github.com/esphome/esphome/commit/be965a60eba6bb769e2a5afdbc8eed132f077a59
- https://github.com/esphome/esphome
- https://github.com/pypa/advisory-database/tree/main/vulns/esphome/PYSEC-2021-351.yaml
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N- Weakness (CWE)
CWE-306- Platform
- Python (PyPI)
- Package
esphome- Disclosed
- 28.09.2021
- Updated
- 11.10.2026 12:19
Sources and licenses
OSV / GitHub Advisory Database - PYSEC-2021-351 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-48mj-p7x2-5jfm - CC BY 4.0
Vulnerability history: esphome
All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 6
- First → latest
- 09.2021 01.2026
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- High 4
- Medium 2
Disclosures per year
- 2021: 1
- 2022: 0
- 2023: 0
- 2024: 3
- 2025: 1
- 2026: 1
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