CVE-2025-27840
What it is
Espressif ESP32 chips allow 29 hidden HCI commands, such as 0xFC02 (Write memory).
At a glance
- Exploitability
- Can be exploited with physical access with an admin-level account. High risk of data exposure, data tampering.
- Exploit odds
- 1.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- No patch or advisory is linked yet. Look at mitigations or restrict exposure.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 1.4% in the next 30 days (EPSS).
- Severity: 6.8 MEDIUM (CVSS).
- Fix: none linked yet, which raises it.
Details
- Published
- Last modified
- Exploit probability
- 1.4% · EPSS, next 30 days
- Weakness
- CWE-912
- Record status
- Analyzed
Affected
- Espressif esp32 Firmware
Attack profile CVSS 3.1 · 6.8
- Attack vector
- Physical
- Complexity
- High
- Privileges needed
- High
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- Low
Raw vector
CVSS:3.1/AV:P/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:L
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2025-27840.md and follow it. Check whether this project is affected by CVE-2025-27840. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
References
- 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