CVE-2021-41104

web_server allows OTA update without checking user defined basic auth username & password

Description

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`.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.28%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: esphome esphome
Published at:
Updated at:

References

Link Tags
https://github.com/esphome/esphome/security/advisories/GHSA-48mj-p7x2-5jfm third party advisory patch
https://github.com/esphome/esphome/pull/2409/commits/207cde1667d8c799a197b78ca8a5a14de8d5ca1e third party advisory patch
https://github.com/esphome/esphome/releases/tag/2021.9.2 third party advisory release notes

Frequently Asked Questions

What is the severity of CVE-2021-41104?
CVE-2021-41104 has been scored as a high severity vulnerability.
How to fix CVE-2021-41104?
To fix CVE-2021-41104, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-41104 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-41104 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-41104?
CVE-2021-41104 affects esphome esphome.
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