Vulnerability · Published Mar 8, 2025 · Assigned by mitre
CVE-2025-27840
Medium 6.8
In plain English
A medium-severity security flaw in ESP32 from Espressif. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.4% (higher than 72% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.
Severity (CVSS 3.1)6.8Medium
Exploit odds (30 days)1.4%top 28.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack tooling1Public PoC
Official description
Espressif ESP32 chips allow 29 hidden HCI commands, such as 0xFC02 (Write memory).
Affected products (as reported)
Weakness: CWE-912 · Vector: CVSS:3.1/AV:P/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:L
References
- https://github.com/TarlogicSecurity/Talks/blob/main/2025_RootedCon_BluetoothTools.pdf
- https://x.com/pascal_gujer/status/1898442439704158276
- https://www.tarlogic.com/news/backdoor-esp32-chip-infect-ot-devices/
- https://www.bleepingcomputer.com/news/security/undocumented-backdoor-found-in-bluetooth-chip-used-by-a-billion-devices/
- https://reg.rootedcon.com/cfp/schedule/talk/5
- https://flyingpenguin.com/?p=67838
- https://github.com/em0gi/CVE-2025-27840
- https://github.com/orgs/espruino/discussions/7699
- https://www.bleepingcomputer.com/news/security/undocumented-commands-found-in-bluetooth-chip-used-by-a-billion-devices/
- https://darkmentor.com/blog/esp32_non-backdoor/
- https://news.ycombinator.com/item?id=43308740
- https://news.ycombinator.com/item?id=43301369
- https://github.com/esphome/esphome/discussions/8382
- https://cheriot.org/auditing/backdoor/2025/03/09/no-esp32-style-backdoor.html
- https://www.espressif.com/en/news/Response_ESP32_Bluetooth