CVE-2021-42300

Privileged device-state tampering

Published Nov 10, 2021 · Updated Aug 19, 2026

Tampering in Microsoft Azure Sphere before 21.10 allows local users with high privileges to modify protected device state. Microsoft has not published the affected component or the operation that improperly accepts or applies attacker-controlled data. Exploitation requires high local privileges and crosses a security boundary; the documented impact is integrity loss without confidentiality or availability impact.

CVSS severity6.0
Medium
EPSS probability0.62%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Tampering in Microsoft Azure Sphere before 21.10 allows local users with high privileges to modify protected device state. Microsoft has not published the affected component or the operation that improperly accepts or applies attacker-controlled data. Exploitation requires high local privileges and crosses a security boundary; the documented impact is integrity loss without confidentiality or availability impact.

The record

CVE
CVE-2021-42300
Published
Nov 10, 2021
Updated
Aug 19, 2026
Vendor
Microsoft
Product
Azure Sphere
Classifications
Unavailable
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Nov 10, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=20.00 <22.07

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Microsoft · Azure Sphereversion=20.00 <22.07

Published CVSS scores

6.7NIST NVDCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
6.0Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:N
5.2Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:N/E:U/RL:O/RC:C
4.6NIST NVDAV:L/AC:L/Au:N/C:P/I:P/A:P

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)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

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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