CVE-2025-20939

Device identifier modification via unauthorized wireless download

Published Apr 8, 2025 · Updated Apr 8, 2025

Improper authorization in Galaxy Watch before SMR Apr-2025 Release 1 allows physically proximate attackers to alter its unique device identifier. The wireless download protocol accepts an identifier update without properly verifying its cryptographic signature, so authorization is not established. Physical access and user interaction are required, and the demonstrated consequence is unauthorized device-identity modification.

CVSS severity5.4
Medium
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in Galaxy Watch before SMR Apr-2025 Release 1 allows physically proximate attackers to alter its unique device identifier. The wireless download protocol accepts an identifier update without properly verifying its cryptographic signature, so authorization is not established. Physical access and user interaction are required, and the demonstrated consequence is unauthorized device-identity modification.

The record

CVE
CVE-2025-20939
Published
Apr 8, 2025
Updated
Apr 8, 2025
Vendor
Samsung Electronics Co., Ltd.
Product
Samsung Mobile Devices
Classifications
CWE-347, T1565.001
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 8, 2025CVE publishedPublication date reported by the CVE source.
  2. Apr 8, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

Samsung Electronics Co., Ltd. · Samsung Mobile DevicesAffected versions are unavailable in this record.

Published CVSS scores

5.4Samsung MobileCVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorphysical
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-347Improper Verification of Cryptographic Signature
T1565.001Stored Data Manipulation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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