Vulnerability · Published Feb 6, 2026 · Assigned by GitHub_M
CVE-2026-25592Semantic Kernel has an Arbitrary File Write via AI Agent Function Calling in .NET SDK
Critical 10.0
In plain English
A critical-severity path traversal in semantic-kernel from microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 2.5% (higher than 85% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| NuGet | microsoft.semantickernel.core | 1.71.0 | GHSA-2ww3-72rp-wpp4 |
| PyPI | semantic-kernel | 1.39.3 | GHSA-2ww3-72rp-wpp4 |
| PyPI | semantic-kernel | 1.39.3 | PYSEC-2026-531 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| microsoft | semantic-kernel | < 1.71.0 |
Weakness: CWE-22 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
References
- https://github.com/microsoft/semantic-kernel/security/advisories/GHSA-2ww3-72rp-wpp4 x_refsource_CONFIRM
- https://github.com/microsoft/semantic-kernel/pull/13478/changes#diff-88d3cacba2bfa84eef8f2aa171b34f9940338cbb784a3ffc49f5fe3af1b8943d x_refsource_MISC
- https://github.com/microsoft/semantic-kernel/blob/main/dotnet/samples/Demos/CodeInterpreterPlugin/Program.cs#L61-L64 x_refsource_MISC