CVE-2026-25592

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?
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.

References

Are there any links users can visit to find out more?

• Sample showing safe use of the CodeInterpreterPlugin
• PR to Add file upload security controls to SessionsPythonPlugin

What kind of vulnerability is it? Who is impacted?
An Arbitrary File Write vulnerability has been identified in Microsoft's Semantic Kernel .NET SDK, specifically within the SessionsPythonPlugin.
Developers who have built applications which include Microsoft's Semantic Kernel .NET SDK and are using the SessionsPythonPlugin

Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.

CVE-2026-25592 has a CVSS score of 9.9 (Critical). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.39.3, 1.71.0); upgrading removes the vulnerable code path.

Kodem intelligence

Has the problem been patched? What versions should users upgrade to?
The problem has been fixed in Microsoft.SemanticKernel.Plugins.Core version 1.71.0. Users should upgrade to version 1.71.0 or higher.

1. What is CVE-2026-25592? CVE-2026-25592 is a critical-severity path traversal vulnerability in semantic-kernel (pip), affecting versions < 1.39.3. It is fixed in 1.39.3, 1.71.0. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.
2. How severe is CVE-2026-25592? CVE-2026-25592 has a CVSS score of 9.9 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which packages are affected by CVE-2026-25592?
   • semantic-kernel (pip) (versions < 1.39.3)
   • Microsoft.SemanticKernel.Core (nuget) (versions < 1.71.0)
4. Is there a fix for CVE-2026-25592? Yes. CVE-2026-25592 is fixed in 1.39.3, 1.71.0. Upgrade to this version or later.
5. Is CVE-2026-25592 exploitable, and should I be worried? Whether CVE-2026-25592 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-25592 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-25592?
   • Upgrade semantic-kernel to 1.39.3 or later
   • Upgrade Microsoft.SemanticKernel.Core to 1.71.0 or later