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TI-2021-17945 Aliases CVE-2021-41104GHSA-48mj-p7x2-5jfm

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

Priority LOW 35CWE-306Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-306.

Summary

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`.

Why it matters now

EPSS 0.01213 68th percentileScored 2026-11-07
Fix Fixed esphome (esphome): 2021.9.2esphome (PyPI): 2021.9.2

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
esphomeesphomebefore 2021.9.22021.9.2Patch availableCNA
—esphome (PyPI)before 2021.9.22021.9.2Patch availableGHSA-48mj-p7x2-5jfm
  • esphome Vendoresphome Affected before 2021.9.2 Fixed in 2021.9.2 Patch available CNA
  • esphome (PyPI) Vendor— Affected before 2021.9.2 Fixed in 2021.9.2 Patch available GHSA-48mj-p7x2-5jfm

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:o:esphome:esphome_firmware:*:*:*:*:*:*:*:*before 2021.9.2Vulnerableesphome
cpe:2.3:h:espressif:esp32:-:*:*:*:*:*:*:*not specified by NVDRunning onespressif
cpe:2.3:h:espressif:esp8266:-:*:*:*:*:*:*:*not specified by NVDRunning onespressif
  • cpe:2.3:o:esphome:esphome_firmware:*:*:*:*:*:*:*:* Versions before 2021.9.2 Vulnerable ·esphome
  • cpe:2.3:h:espressif:esp32:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·espressif
  • cpe:2.3:h:espressif:esp8266:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·espressif

Remediation

  • Fix · CNA esphome (esphome) Fixed in 2021.9.2
  • Fix · GHSA-48mj-p7x2-5jfm esphome (PyPI) Fixed in 2021.9.2 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-41104
  2. 2026-10-03 Alias added: GHSA-48mj-p7x2-5jfm

References

Patch 2

Advisory 2

Other 5

  • TI-2025-35691 ESP-IDF web_server basic auth bypass using empty or incomplete Authorization header CVSS 3.1HIGH 8.1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences