CVE-2026-25592: Microsoft Semantic-Kernel

Critical severity, CVSS 9.9. EPSS: 2.4% chance of exploitation in the next 30 days.

Semantic Kernel is an SDK used to build, orchestrate, and deploy AI agents and multi-agent systems. Prior to 1.71.0, an Arbitrary File Write vulnerability has been identified in Microsoft's Semantic Kernel .NET SDK, specifically within the SessionsPythonPlugin. The problem has been fixed in Microsoft.SemanticKernel.Core version 1.71.0. As a mitigation, users can create a Function Invocation Filter which checks the arguments being passed to any calls to DownloadFileAsync  or UploadFileAsync and ensures the provided localFilePath is allow listed.

Affected products

• Microsoft Semantic-Kernel: before 1.71.0 (fixed in 1.71.0)

Published 2026-02-06. Last modified 2026-06-17.