CVE-2021-41104— web_server allows OTA update without checking user defined basic auth username & password
Quick assessment
Affected
esphome esphome
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Esphome是一个配置、管理智能硬件的系统。用于控制Esp8266/Esp32硬件，实现家庭自动化控制。 ESPHome 2021.9.1及之前版本存在访问控制错误漏洞，该漏洞源于用户容易受到"web_server"允许无线(OTA)更新而无需检查用户定义的基本身份验证用户名和密码的问题。
Possible ATT&CK Techniques 2 AI
T1574 · Hijack Execution Flow T1059 · Command and Scripting Interpreter
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I. Basic Information for CVE-2021-41104
Vulnerability Information
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Vulnerability Title
web_server allows OTA update without checking user defined basic auth username & password
Source: CVE Program / CVE List V5
Vulnerability 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`.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
关键功能的认证机制缺失
Source: CVE Program / CVE List V5
Vulnerability Title
Esphome 访问控制错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Esphome是一个配置、管理智能硬件的系统。用于控制Esp8266/Esp32硬件，实现家庭自动化控制。 ESPHome 2021.9.1及之前版本存在访问控制错误漏洞，该漏洞源于用户容易受到"web_server"允许无线(OTA)更新而无需检查用户定义的基本身份验证用户名和密码的问题。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
II. Public POCs for CVE-2021-41104
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Patches & Fixes for CVE-2021-41104 (1)
Vendor Advisories for CVE-2021-41104 (1)
-
https://github.com/esphome/esphome/security/advisories/GHSA-48mj-p7x2-5jfm x_refsource_CONFIRM
Other References for CVE-2021-41104 (1)
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https://github.com/esphome/esphome/releases/tag/2021.9.2 x_refsource_MISC
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V. Comments for CVE-2021-41104
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