CVE-2025-57808: Esphome Firmware

High severity, CVSS 8.1. EPSS: 1.6% chance of exploitation in the next 30 days.

ESPHome is a system to control microcontrollers remotely through Home Automation systems. In version 2025.8.0 in the ESP-IDF platform, ESPHome's web_server authentication check can pass incorrectly when the client-supplied base64-encoded Authorization value is empty or is a substring of the correct value. This allows access to web_server functionality (including OTA, if enabled) without knowing any information about the correct username or password. This issue has been patched in version 2025.8.1.

Affected products

• Esphome Esphome Firmware: version 2025.8.0 only

Published 2025-09-02. Last modified 2026-06-17.