CVE-2021-41104 - CVE House
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Status published High CVE-2021-41104

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

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`.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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CVE-2024-29019
ESPHome vulnerable to Authentication bypass via Cross site request forgery
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CVE-2024-27287
ESPHome vulnerable to stored Cross-site Scripting in edit configuration file API
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CVE-2024-27081
ESPHome remote code execution via arbitrary file write
High 7.2

Affected Vendor

Affected Software

esphome
Vulnerable Versions:
< 2021.9.2

Timeline

Official Publish: September 28th, 2021
Last Modified: August 4th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Weaknesses (CWE)

CWE-306

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1078 Valid Accounts
Persistence
T1136 Create Account
Persistence
T1098 Account Manipulation
Privilege Escalation
T1021 Remote Services
Lateral Movement