CVE-2021-41104: Basic auth bypass in esphome

CVE-2021-41104 · Severity: low · CVSS 3.1 · Published 2021-09-28

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`.

Technologies: esphome (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2021-41104 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2021-41104 being exploited in the wild.
How severe is CVE-2021-41104?
Low severity, with a CVSS score of 3.1, published 28 September 2021.
Which products and versions are affected?
esphome (PyPI) ECOSYSTEM:introduced=0,fixed=2021.9.2, GIT:introduced=0,fixed=2234f6aacf8cc653307fed80f3750317a82c4f83|ECOSYSTEM:introduced=0,fixed=2021.9.2.
Is there a fix for CVE-2021-41104?
Yes. esphome (PyPI): upgrade to 2021.9.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2021-41104?
Check whether you run esphome (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • esphome (PyPI): upgrade to 2021.9.2 or later
    pip install "esphome>=2021.9.2"

Affected products

  • esphome (PyPI) ECOSYSTEM:introduced=0,fixed=2021.9.2, GIT:introduced=0,fixed=2234f6aacf8cc653307fed80f3750317a82c4f83|ECOSYSTEM:introduced=0,fixed=2021.9.2

Identifiers

  • CVE-2021-41104
  • GHSA-48mj-p7x2-5jfm
  • PYSEC-2021-351

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