High severity · published Sep 28, 2021
CVE-2021-41104
ESPHome is a system to control the ESP8266/ESP32
7.5
CVSS
1.2%
EPSS
No
On KEV
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`.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.2% · higher than 68% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EF
Esphome Firmware · Esphome
before 2021.9.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-41104
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-41104
Patch
https://github.com/esphome/esphome/pull/2409/commits/207cde1667d8c799a197b78ca8a5a14de8d5ca1e
Release Notes
https://github.com/esphome/esphome/releases/tag/2021.9.2
Patch
https://github.com/esphome/esphome/security/advisories/GHSA-48mj-p7x2-5jfm
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