CVE-2021-28452Network attack vector

Memory corruption requiring user interaction

Published Apr 13, 2021 · Updated Aug 3, 2024

Memory corruption in affected Microsoft Outlook editions allows remote attackers to cause unspecified impact via unspecified vectors. Microsoft has not published the affected object, parser, input format, or memory operation that causes the corruption. Successful exploitation requires user interaction, and the published assessment does not establish code execution or a more specific consequence.

CVSS severity7.1
High
EPSS probability1.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory corruption in affected Microsoft Outlook editions allows remote attackers to cause unspecified impact via unspecified vectors. Microsoft has not published the affected object, parser, input format, or memory operation that causes the corruption. Successful exploitation requires user interaction, and the published assessment does not establish code execution or a more specific consequence.

The record

CVE
CVE-2021-28452
Published
Apr 13, 2021
Updated
Aug 3, 2024
Vendor
Microsoft
Product
Microsoft Office 2019
Classifications
CWE-787, T1204
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 13, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record 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=19.0.0 <https://aka.ms/OfficeSecurityReleases

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Microsoft · Microsoft Office 2019version=19.0.0 <https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Outlook 2016version=16.0.0.0 <publication
Microsoft · Microsoft Outlook 2013version=15.0.0.0 <publication
Microsoft · Microsoft Outlook 2010version=13.0.0.0 <publication
Microsoft · Microsoft 365 Apps for enterpriseversion=16.0.1 <https://aka.ms/OfficeSecurityReleases

Published CVSS scores

7.1Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
7.8NIST NVDCVSS: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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1204User 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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