CVE-2021-43875

Code execution via glTF integer overflow

Published Dec 15, 2021 · Updated Aug 4, 2024

Integer overflow in the glTF-SDK component in Microsoft Office allows remote attackers to execute code via a malicious page or file. The component inadequately validates user-supplied graphics data, allowing an integer overflow before a memory write. Exploitation requires the target to visit a malicious page or open a malicious file, and code runs in the current process context.

CVSS severity7.8
High
EPSS probability5.10%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer overflow in the glTF-SDK component in Microsoft Office allows remote attackers to execute code via a malicious page or file. The component inadequately validates user-supplied graphics data, allowing an integer overflow before a memory write. Exploitation requires the target to visit a malicious page or open a malicious file, and code runs in the current process context.

The record

CVE
CVE-2021-43875
Published
Dec 15, 2021
Updated
Aug 4, 2024
Vendor
Microsoft
Product
Microsoft Office 2019
Classifications
T1204.002, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record 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=19.0.0 <https://aka.ms/OfficeSecurityReleases

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Microsoft · Microsoft Office 2019version=19.0.0 <https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office LTSC for Mac 2021version=16.0.1 <16.56.21121100
Microsoft · Microsoft Office 2019 for Macversion=16.0.0 <16.56.21121100
Microsoft · Microsoft Office LTSC 2021version=16.0.1 <https://aka.ms/OfficeSecurityReleases
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
7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1204.002User Execution: Malicious File
T1203Exploitation for Client Execution

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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