[NEW] [medium] Microsoft Defender for Endpoint: Vulnerability enables Information Disclosure

mediumCVE-2026-54123

A local attacker can exploit a vulnerability in Microsoft Defender for Endpoint to disclose information.

CSIRTS triage

vendor: Microsoft product: Defender for Endpoint Information disclosure

What: A vulnerability in Microsoft Defender for Endpoint allows local attackers to disclose information.
Who is affected: Systems running Defender for Endpoint are exposed to local information disclosure.
Urgency: Medium priority; requires local access but impacts security product integrity.
Action: Apply Microsoft security updates for Defender for Endpoint.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: CERT-Bund (BSI) Security Advisories (DE · national-cert · site)
Severity: medium
Published: 2026-08-12
Exploitation: Not in CISA KEV at last sync
Language: Machine-translated to English — verify against the original

Original advisory: https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-2778

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-541230.45% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 37% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-54123	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

Recent advisories for Microsoft Defender for Endpoint

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

mediumCVE-2026-54123: Exposure of sensitive information to an unauthorized actor in Microsoft Defender for Endpoint …nvd · 2026-08-11
mediumCVE-2026-54123: Microsoft Defender for Endpoint for Mac Information Disclosure Vulnerabilitymsrc · 2026-08-11
mediumCVE-2026-56178: Time-of-check time-of-use (toctou) race condition in Microsoft Defender for Endpoint allows an…nvd · 2026-07-14
mediumCVE-2026-56178: Microsoft Defender for Endpoint for Mac Elevation of Privilege Vulnerabilitymsrc · 2026-07-14
mediumCVE-2026-50657: Microsoft Defender for Endpoint for Mac Information Disclosure Vulnerabilitymsrc · 2026-07-14
highCVE-2026-50658: Microsoft Defender for Endpoint for Mac Elevation of Privilege Vulnerabilitymsrc · 2026-07-14