CriticalVulnerability

CVE-2026-25592: Semantic Kernel .NET SDK arbitrary file write in SessionsPythonPlugin

Source: NVD(opens in a new tab)
Identifier: CVE-2026-25592
Published: February 6, 2026
Record updated: October 20, 2026

Affected: semantic-kernel < 1.39.3, fixed in 1.39.3, released February 1, 2026, 5 days before disclosure
Microsoft.SemanticKernel.Core < 1.71.0, fixed in 1.71.0
Known exploitation: Not listed in the CISA Known Exploited Vulnerabilities catalog at the last check.
EPSS: 2.5%

Summary

Semantic Kernel's .NET SDK, prior to 1.70.0, contains an Arbitrary File Write vulnerability in the SessionsPythonPlugin. The flaw is fixed in Microsoft.SemanticKernel.Core 1.70.0.

Mitigation

Fixed in Microsoft.SemanticKernel.Core 1.70.0. As a mitigation, create a Function Invocation Filter that checks the arguments passed to DownloadFileAsync or UploadFileAsync and ensures the provided localFilePath is allow listed.

Details

Scores and exploitation

CVSS score: 9.9(critical)
Patch available: Yes
EPSS: 2.5%Estimated probability that this CVE is exploited in the next 30 days, from the FIRST Exploit Prediction Scoring System. Read on November 4, 2026.

Weaknesses and techniques

Weakness (CWE): CWE-22
Attack pattern (CAPEC): CAPEC-126

Affected

Packages: semantic-kernel@< 1.39.3 (fixed: 1.39.3)
Microsoft.SemanticKernel.Core@< 1.71.0 (fixed: 1.71.0)
Vendors: Microsoft

Classification

Attack type: Other
Attack sophistication: Moderate
AI component targeted: Framework
Impact: Integrity,
Availability
Labels: security

How this record was produced

Summaries, mitigations and labels on this page are generated automatically from the source. The linked source is authoritative. The source gives this advisory a description and no title, so the title above is a headline generated from the source text.

Original source: https://nvd.nist.gov/vuln/detail/CVE-2026-25592

First tracked: February 15, 2026 at 08:36 PM ET, from NVD/CVE Database

Classifier: claude-haiku-5-5, prompt v4

Classifier confidence: 95% (self-assessed)

Affected packages in the Exposure Registry

Matched by package name and ecosystem. Each entry shows whether the package delegates to a language model and how many tracked packages depend on it.

semantic-kernelPyPILLM dependency since 2023-04-11 · 3 tracked dependents

Coverage

News, research and other items that mention CVE-2026-25592.

GenAI and Agentic AI Exploit Roundup Q2 2026OWASP GenAI Security · 2026-07-09

Topics

AI agents

Summary

Mitigation

Affected packages in the Exposure Registry

Coverage

Topics

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