CVE-2023-21721Network attack vector

Authenticated elevation of privilege

Published Feb 14, 2023 · Updated Aug 19, 2026

Improper authentication in Microsoft OneNote for Android before 16.0.16026.20158 allows remote authenticated users to elevate privileges. Microsoft has not disclosed the affected authentication locus or the operation that fails to validate an identity. Exploitation requires network access and low privileges, and the published impact is limited to unauthorized modification without disclosure or service interruption.

CVSS severity6.5
Medium
EPSS probability0.88%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in Microsoft OneNote for Android before 16.0.16026.20158 allows remote authenticated users to elevate privileges. Microsoft has not disclosed the affected authentication locus or the operation that fails to validate an identity. Exploitation requires network access and low privileges, and the published impact is limited to unauthorized modification without disclosure or service interruption.

The record

CVE
CVE-2023-21721
Published
Feb 14, 2023
Updated
Aug 19, 2026
Vendor
Microsoft
Product
Microsoft OneNote for Android
Classifications
CWE-287
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 14, 2023CVE 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

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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=16.0.1 <16.0.16026.20158

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Microsoft · Microsoft OneNote for Androidversion=16.0.1 <16.0.16026.20158

Published CVSS scores

6.5Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/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)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication

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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