CVE-2025-21361

Code execution via improperly restricted resource names

Published Jan 14, 2025 · Updated Jun 9, 2026

Improper resource-name restriction in Microsoft Outlook for Mac before 16.93 allows attackers to execute code after user interaction. Microsoft identifies improper restriction of file or resource names but has not disclosed the affected parser or its unsafe operation. Exploitation requires interaction with attacker-controlled content, and successful code runs with the victim's privileges.

CVSS severity7.8
High
EPSS probability0.75%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper resource-name restriction in Microsoft Outlook for Mac before 16.93 allows attackers to execute code after user interaction. Microsoft identifies improper restriction of file or resource names but has not disclosed the affected parser or its unsafe operation. Exploitation requires interaction with attacker-controlled content, and successful code runs with the victim's privileges.

The record

CVE
CVE-2025-21361
Published
Jan 14, 2025
Updated
Jun 9, 2026
Vendor
Microsoft
Product
Microsoft Office LTSC for Mac 2024
Classifications
CWE-641, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 14, 2025CVE publishedPublication date reported by the CVE source.
  2. Jun 9, 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=16.0.0 <16.93.25011212

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Microsoft · Microsoft Office LTSC for Mac 2024version=16.0.0 <16.93.25011212
Microsoft · Microsoft Office LTSC for Mac 2021version=16.0.1 <16.93.25011212
Microsoft · Microsoft Outlook for Macversion=1.0.0 <16.93

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-641Improper Restriction of Names for Files and Other Resources
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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