CVE-2026-54123

Sensitive information disclosure to local users

Published Aug 11, 2026 · Updated Aug 25, 2026

Information disclosure in Microsoft Defender for Endpoint for Mac before 101.26042.0020 allows local users to read sensitive data. Microsoft has described only an exposure of sensitive information to an unauthorized actor and has not publicly identified the file, service, log, or API in the macOS agent that returns the data. Reachability requires local authenticated access on a Mac running the Defender agent, and the published scoring bounds the impact to confidentiality rather than tampering or code execution.

CVSS severity5.5
Medium
EPSS probability0.44%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Microsoft Defender for Endpoint for Mac before 101.26042.0020 allows local users to read sensitive data. Microsoft has described only an exposure of sensitive information to an unauthorized actor and has not publicly identified the file, service, log, or API in the macOS agent that returns the data. Reachability requires local authenticated access on a Mac running the Defender agent, and the published scoring bounds the impact to confidentiality rather than tampering or code execution.

The record

CVE
CVE-2026-54123
Published
Aug 11, 2026
Updated
Aug 25, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-200
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 11, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 25, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.5Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor

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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