CVE-2025-15645

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.

CVSS v3 4.6 MEDIUM

4.6^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 0.9 / Impact : 3.6

Attack Vector PHYSICAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://donjon.ledger.com/lsb/021/
https://www.vulncheck.com/advisories/ledger-nano-x-flex-stax-mcu-firmware-update-denial-of-service

Configurations

No configuration.

History

20 May 2026, 14:16

Type	Values Removed	Values Added
References	~~{'url': 'https://www.ledger.com/security-bulletin', 'source': 'disclosure@vulncheck.com'}~~	() https://donjon.ledger.com/lsb/021/ -

19 May 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-19 22:16

Updated : 2026-05-20 14:16

NVD link : CVE-2025-15645

Mitre link : CVE-2025-15645

CVE.ORG link : CVE-2025-15645

JSON object : View

Products Affected

No product.

CWE

CWE-1284

Improper Validation of Specified Quantity in Input

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