CVE-2025-57808

ESP-IDF web_server basic auth bypass using empty or incomplete Authorization header

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

esphome

CVSS v3.1 GITHUB

8.1 HIGHCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS

1.63% chance of exploitation in the next 30 days, 76th percentile

Nuclei

high

Published

2025-09-02

Proof-of-concept exploits (2)

• esphome/esphome/security/advisories/GHSA-mxh2-ccgj-8635
• advisories/GHSA-mxh2-ccgj-8635

Nuclei templates (1)

• projectdiscovery/nuclei-templates/blob/main/http/cves/2025/CVE-2025-57808.yaml

Security advisories

• esphome/esphome/commit/2aceb56606ec8afec5f49c92e140c8050a6ccbe5

References

• CVE Record
• NVD entry