CVE-2021-35952

Unauthenticated time change via Bluetooth LE handle

Published Dec 26, 2022 · Updated Apr 14, 2025

Improper access control in Fastrack Reflex 2.0 Activity Tracker W307S_REFLEX_v90.89 allows remote attackers to change time via Bluetooth LE. The device accepts writes to Bluetooth LE characteristic handle 0x0017 without pairing or access control, changing the stored time, date, and month. Bluetooth proximity is required, but no authentication or user interaction is needed; the bounded consequence is integrity impact to displayed and recorded time values.

CVSS severity5.3
Medium
EPSS probability0.57%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Fastrack Reflex 2.0 Activity Tracker W307S_REFLEX_v90.89 allows remote attackers to change time via Bluetooth LE. The device accepts writes to Bluetooth LE characteristic handle 0x0017 without pairing or access control, changing the stored time, date, and month. Bluetooth proximity is required, but no authentication or user interaction is needed; the bounded consequence is integrity impact to displayed and recorded time values.

The record

CVE
CVE-2021-35952
Published
Dec 26, 2022
Updated
Apr 14, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1565.002
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 26, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 14, 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 buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
5.3CISA ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

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.

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No observations available

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

Weakness, pattern, technique

T1565.002Transmitted Data Manipulation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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