CVE-2023-21735

Code execution via undisclosed use-after-free

Published Jan 10, 2023 · Updated Feb 28, 2025

Use-after-free in affected Microsoft Office desktop apps allows context-dependent attackers to execute code after user interaction. Microsoft identifies the defect only as a use-after-free and has not disclosed the affected component, incorrect object-lifetime operation, or triggering input. Exploitation requires a local attack path and user interaction; no network-service or direct unauthenticated remote path is described.

CVSS severity7.8
High
EPSS probability0.72%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in affected Microsoft Office desktop apps allows context-dependent attackers to execute code after user interaction. Microsoft identifies the defect only as a use-after-free and has not disclosed the affected component, incorrect object-lifetime operation, or triggering input. Exploitation requires a local attack path and user interaction; no network-service or direct unauthenticated remote path is described.

The record

CVE
CVE-2023-21735
Published
Jan 10, 2023
Updated
Feb 28, 2025
Vendor
Microsoft
Product
Microsoft Office LTSC for Mac 2021
Classifications
CWE-416
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 10, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 28, 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?

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

  1. Affected versionversion=16.0.1 <16.69.23010700

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Microsoft · Microsoft Office LTSC for Mac 2021version=16.0.1 <16.69.23010700
Microsoft · Microsoft Office 2019 for Macversion=16.0.0 <16.69.23010700
Microsoft · Microsoft 365 Apps for enterpriseversion=16.0.1 <https://aka.ms/OfficeSecurityReleases

Published CVSS scores

7.8Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free

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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