CVE-2025-27840

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

08/03/2025

Last modified:

12/03/2025

Description

Espressif ESP32 chips allow 29 hidden HCI commands, such as 0xFC02 (Write memory).

Impact

Vector 3.x

CVSS:3.1/AV:P/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:L CVSS v3.1 Severity and Metrics:

Base Score: 6.80 MEDIUM
Vector: CVSS:3.1/AV:P/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:L

Attack Vector (AV): Physical
Attack Complexity (AC): High
Privileges Required (PR): High
User Interaction (UI): None
Scope (S): Changed
Confidentiality (C): High
Integrity (I): High
Availability (A): Low

Base Score 3.x

6.80

Severity 3.x

MEDIUM

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:o:espressif:esp32_firmware:-:::::::*
cpe:2.3:h:espressif:esp32:-:::::::*

To consult the complete list of CPE names with products and versions, see this page

References to Advisories, Solutions, and Tools

https://cheriot.org/auditing/backdoor/2025/03/09/no-esp32-style-backdoor.html
https://darkmentor.com/blog/esp32_non-backdoor/
https://flyingpenguin.com/?p=67838
https://github.com/TarlogicSecurity/Talks/blob/main/2025_RootedCon_BluetoothTools.pdf
https://github.com/em0gi/CVE-2025-27840
https://github.com/esphome/esphome/discussions/8382
https://github.com/orgs/espruino/discussions/7699
https://news.ycombinator.com/item?id=43301369
https://news.ycombinator.com/item?id=43308740
https://reg.rootedcon.com/cfp/schedule/talk/5
https://www.bleepingcomputer.com/news/security/undocumented-backdoor-found-in-bluetooth-chip-used-by-a-billion-devices/
https://www.bleepingcomputer.com/news/security/undocumented-commands-found-in-bluetooth-chip-used-by-a-billion-devices/
https://www.espressif.com/en/news/Response_ESP32_Bluetooth
https://www.tarlogic.com/news/backdoor-esp32-chip-infect-ot-devices/
https://x.com/pascal_gujer/status/1898442439704158276