Ledger Nano X/Flex/Stax up to 2.4.1 MCU Firmware Update reset_handler improper validation of specified quantity in input

CVSS Meta Temp Score
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CTI Interest Score
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4.5$0-$5k0.00

Summaryinfo

A vulnerability was found in Ledger Nano X, Flex and Stax up to 2.4.1 and classified as problematic. This affects an unknown function of the component MCU Firmware Update Handler. The manipulation of the argument reset_handler results in improper validation of specified quantity in input. This vulnerability is identified as CVE-2025-15645. An attack on the physical device is feasible. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Ledger Nano X, Flex and Stax up to 2.4.1. Affected is an unknown code of the component MCU Firmware Update Handler. The manipulation of the argument reset_handler with an unknown input leads to a improper validation of specified quantity in input vulnerability. CWE is classifying the issue as CWE-1284. The product receives input that is expected to specify a quantity (such as size or length), but it does not validate or incorrectly validates that the quantity has the required properties. This is going to have an impact on availability. CVE summarizes:

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.

The weakness was released by Guanxing Wen. The advisory is available at ledger.com. This vulnerability is traded as CVE-2025-15645 since 05/19/2026. The exploitability is told to be easy. Local access is required to approach this attack. The exploitation doesn't require any form of authentication. Technical details are known, but there is no available exploit.

Upgrading to version 2.4.2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-209901). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.6
VulDB Meta Temp Score: 4.5

VulDB Base Score: 4.6
VulDB Temp Score: 4.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.6
CNA Vector (VulnCheck): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper validation of specified quantity in input
CWE: CWE-1284 / CWE-703
CAPEC: 🔒
ATT&CK: 🔒

Physical: Yes
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Nano X/Flex/Stax 2.4.2

Timelineinfo

05/19/2026 CVE reserved
05/19/2026 +0 days VulDB entry created
05/20/2026 +0 days Advisory disclosed
05/20/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: ledger.com
Researcher: Guanxing Wen
Status: Confirmed

CVE: CVE-2025-15645 (🔒)
GCVE (CVE): GCVE-0-2025-15645
GCVE (VulDB): GCVE-100-364746
EUVD: 🔒

Entryinfo

Created: 05/20/2026 00:32
Updated: 05/20/2026 01:34
Changes: 05/20/2026 00:32 (77), 05/20/2026 01:34 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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