CVE-2024-21426

Code execution via undisclosed use-after-free

Published Mar 12, 2024 · Updated May 3, 2025

Use-after-free in Microsoft SharePoint Server 2016, 2019, and Subscription Edition allows local users to execute code after user interaction. Microsoft identifies the weakness but has not disclosed the affected component, object-lifetime operation, or crafted input that triggers reuse. A local attack path and user action are required; successful exploitation runs code in the affected SharePoint process.

CVSS severity7.8
High
EPSS probability3.90%
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 Microsoft SharePoint Server 2016, 2019, and Subscription Edition allows local users to execute code after user interaction. Microsoft identifies the weakness but has not disclosed the affected component, object-lifetime operation, or crafted input that triggers reuse. A local attack path and user action are required; successful exploitation runs code in the affected SharePoint process.

The record

CVE
CVE-2024-21426
Published
Mar 12, 2024
Updated
May 3, 2025
Vendor
Microsoft
Product
Microsoft SharePoint Enterprise Server 2016
Classifications
CWE-416
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 12, 2024CVE publishedPublication date reported by the CVE source.
  2. May 3, 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=16.0.0 <16.0.5439.1000

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Microsoft · Microsoft SharePoint Enterprise Server 2016version=16.0.0 <16.0.5439.1000
Microsoft · Microsoft SharePoint Server 2019version=16.0.0 <16.0.10408.20000
Microsoft · Microsoft SharePoint Server Subscription Editionversion=16.0.0 <16.0.17328.20136

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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