What’s Vulnerable › Vulnerabilities

CVE-2026-26030: Microsoft Semantic Kernel InMemoryVectorStore filter functionality vulnerable to remote code execution

• Severity: critical (CVSS 10.0 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-02-19 · updated 2026-06-17
• Weakness: CWE-94

Description

Semantic Kernel, Microsoft's semantic kernel Python SDK, has a remote code execution vulnerability in versions prior to 1.39.4, specifically within the `InMemoryVectorStore` filter functionality. The problem has been fixed in version `python-1.39.4`. Users should upgrade this version or higher. As a workaround, avoid using `InMemoryVectorStore` for production scenarios.

Affected products

• microsoft semantic-kernel: before 1.39.4 — fixed in 1.39.4
• microsoft semantic-kernel: before 1.39.4

How to fix

Upgrade to a fixed version: microsoft semantic-kernel 1.39.4. Check the vendor advisory for mitigations.

References

• https://github.com/microsoft/semantic-kernel/pull/13505
• https://github.com/microsoft/semantic-kernel/releases/tag/python-1.39.4
• https://github.com/microsoft/semantic-kernel/security/advisories/GHSA-xjw9-4gw8-4rqx

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