CVE-2026-21219

Local code execution via use-after-free

Published Jan 13, 2026 · Updated Jan 13, 2026

Use-after-free in Inbox COM Objects in Microsoft Windows SDK before 10.0.26100.7463 allows local users to execute arbitrary code. Microsoft identifies global memory as the affected locus but has not disclosed which COM object frees it prematurely or how attacker-controlled data reaches the stale reference. Exploitation requires local access and user interaction, and successful execution runs in the vulnerable application's context.

CVSS severity7.0
High
EPSS probability0.38%
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 Inbox COM Objects in Microsoft Windows SDK before 10.0.26100.7463 allows local users to execute arbitrary code. Microsoft identifies global memory as the affected locus but has not disclosed which COM object frees it prematurely or how attacker-controlled data reaches the stale reference. Exploitation requires local access and user interaction, and successful execution runs in the vulnerable application's context.

The record

CVE
CVE-2026-21219
Published
Jan 13, 2026
Updated
Jan 13, 2026
Vendor
Microsoft
Product
Windows SDK
Classifications
CWE-416, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 13, 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=26100 <10.0.26100.7463

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Microsoft · Windows SDKversion=26100 <10.0.26100.7463

Published CVSS scores

7.0Microsoft CorporationCVSS:3.1/AV:L/AC:H/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.

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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
T1204.002Malicious File

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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