CVE-2026-20435

Device identifier disclosure via preloader logic error

Published Mar 2, 2026 · Updated Mar 2, 2026

Information disclosure in MediaTek Preloader allows physically proximate attackers to read device unique identifiers from affected chipsets. MediaTek identifies a logic error in the preloader but has not disclosed the responsible routine, data path, or incorrect operation. Physical access is required; no execution privileges or user interaction are needed, and the reported impact is limited to identifier disclosure.

CVSS severity4.6
Medium
EPSS probability0.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in MediaTek Preloader allows physically proximate attackers to read device unique identifiers from affected chipsets. MediaTek identifies a logic error in the preloader but has not disclosed the responsible routine, data path, or incorrect operation. Physical access is required; no execution privileges or user interaction are needed, and the reported impact is limited to identifier disclosure.

The record

CVE
CVE-2026-20435
Published
Mar 2, 2026
Updated
Mar 2, 2026
Vendor
MediaTek
Product
MediaTek Preloader
Classifications
CWE-522, T1005
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 2, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 2, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Android 14.0, 15.0, 16.0 / openWRT 21.02, 23.05 / Yocto 4.0 / RDK-B 22Q3, 24Q1 / Zephyr 3.7.0

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

MediaTek · MediaTek Preloaderversion=Android 14.0, 15.0, 16.0 / openWRT 21.02, 23.05 / Yocto 4.0 / RDK-B 22Q3, 24Q1 / Zephyr 3.7.0

Published CVSS scores

4.6CISA ADPCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/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.

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-522Insufficiently Protected Credentials
T1005Data from Local System

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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