Microsoft disclosed CVE-2026-26155, an information disclosure flaw in the Local Security Authority Subsystem Service (LSASS), and published guidance through its Security Update Guide. LSASS is a core Windows security component responsible for enforcing security policy and handling authentication-related functions, making flaws in the service significant for enterprise defenders even when they do not enable direct code execution.
Microsoft’s advisory links the issue to a previously documented LSASS information disclosure case, CVE-2023-36428, indicating a recurring vulnerability pattern affecting the same Windows security subsystem. Organizations should review Microsoft’s update guidance, identify affected Windows assets, and prioritize remediation and monitoring around systems where exposure of sensitive security information from LSASS could increase follow-on attack risk.

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2 events from the most recent confirmed update back to the earliest known activity.
Microsoft published a Security Update Guide advisory for CVE-2026-26155, another Local Security Authority Subsystem Service information disclosure vulnerability.
Microsoft published a Security Update Guide advisory for CVE-2023-36428, a Local Security Authority Subsystem Service information disclosure vulnerability.
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