High severity · published Sep 2, 2025
CVE-2025-57808
ESP-IDF web_server basic auth bypass using empty or incomplete Authorization header
8.1
CVSS
1.5%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.5% · higher than 75% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ES
esphome · esphome
= 2025.8.0 · source: vendor
EF
Esphome Firmware · Esphome
2025.8.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-57808
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-57808
Patch
https://github.com/esphome/esphome/commit/2aceb56606ec8afec5f49c92e140c8050a6ccbe5
Exploit
https://github.com/esphome/esphome/security/advisories/GHSA-mxh2-ccgj-8635
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