MSRC-CVE-2026-54123 — Microsoft Defender for Endpoint for Mac Information Disclosure Vulnerability

Summary

Impact: Information Disclosure. Microsoft rating: Important. Not known to be exploited — Exploitation Less Likely. Customer action: Required.

Details

What information could be disclosed by successfully exploiting this vulnerability?
An attacker who successfully exploited this vulnerability could view Microsoft Defender for Endpoint configuration exclusion settings that are intended to be viewable only by administrators.

Security updates
101.26042.0020 — https://learn.microsoft.com/en-us/defender-endpoint/mac-updates?view=o365-worldwide

Vulnerabilities 1

Medium 5.5

CVE-2026-54123

Microsoft Defender for Endpoint for Mac Information Disclosure Vulnerability

Exposure of sensitive information to an unauthorized actor in Microsoft Defender for Endpoint allows an authorized attacker to disclose information locally.

Microsoft Microsoft Defender for Endpoint for Mac

Aug 11, 2026

Revision history

2026-08-11 #1
Information published.

References

CVE-2026-54123 Microsoft Defender for Endpoint for Mac Information Disclosure Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-54123
Microsoft Exploitability Index
https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1
Microsoft Support Lifecycle
https://support.microsoft.com/lifecycle
Common Vulnerability Scoring System
https://www.first.org/cvss