Ledger Nano X, Flex, and Stax devices contain a denial of service vulnerability in the MCU firmware update process due to missing validation of the reset_handler parameter during firmware flashing. An attacker can provide a crafted reset_handler address pointing to invalid memory or attacker-controlled code to cause the device to enter an unrecoverable fault state during boot, resulting in permanent loss of operability.
https://www.vulncheck.com/advisories/ledger-nano-x-flex-stax-mcu-firmware-update-denial-of-service
Published: 2026-05-19
Updated: 2026-05-20
Base Score: 4.9
Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:N/A:C
Severity: Medium
Base Score: 4.6
Vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: Medium
Base Score: 5.1
Vector: CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00019