Ledger Nano X, Flex, Stax MCU Firmware Update Denial of Service
Summary
| CVE | CVE-2025-15645 |
|---|---|
| State | PUBLISHED |
| Assigner | VulnCheck |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-19 22:16:36 UTC |
| Updated | 2026-05-20 14:01:24 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v4.0 5.1 MEDIUM from [email protected]
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS: 0.000230000 probability, percentile 0.066860000 (date 2026-05-27)
Problem Types: CWE-1284 | CWE-1284 CWE-1284 Improper Validation of Specified Quantity in Input
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 5.1 | MEDIUM | 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/E:X/C... |
| 4.0 | CNA | CVSS | 5.1 | MEDIUM | 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 |
| 3.1 | [email protected] | Primary | 4.6 | MEDIUM | CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | CVSS | 4.6 | MEDIUM | CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v4.0 Breakdown
Attack Vector
PhysicalAttack Complexity
LowAttack Requirements
NonePrivileges Required
NoneUser Interaction
NoneConfidentiality
NoneIntegrity
NoneAvailability
HighSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS v3.1 Breakdown
Attack Vector
PhysicalAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Ledger | Ledger Nano X | affected 2.4.2 custom | Not specified |
| CNA | Ledger | Ledger Flex | affected 1.2.2 custom | Not specified |
| CNA | Ledger | Ledger Stax | affected 1.6.2 custom | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| Ledger Security Bulletin 021 | https://donjon.ledger.com/lsb/021/ | donjon.ledger.com | vendor-advisory |
| www.vulncheck.com/advisories/ledger-nano-x-flex-stax-mcu-firmware-update-denial... | [email protected] | www.vulncheck.com | |
| www.ledger.com/security-bulletin | [email protected] | www.ledger.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Guanxing Wen (en)
CNA: VulnCheck (en)
There are currently no legacy QID mappings associated with this CVE.