RCE in Microsoft Semantic-Kernel
CVE-2026-26030
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.
Vulnerability class: RCE (Remote Code Execution)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.037 (89.4th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 89.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.037 · newest: 0.037 · change: -0.000
Affected products
- Microsoft Semantic-Kernel — versions < 1.39.4
- Microsoft Semantic Kernel
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/microsoft/semantic-kernel/security/advisories/GHSA-xjw9-4gw8-4rqx (Patch, Vendor Advisory)
- github.com/microsoft/semantic-kernel/pull/13505 (Patch, Issue Tracking)
- github.com/microsoft/semantic-kernel/releases/tag/python-1.39.4 (Release Notes)
Frequently asked questions
- What is CVE-2026-26030?
- CVE-2026-26030 is a critical-severity vulnerability in Microsoft Semantic-Kernel, classified under Code Injection. CVSS score: 9.9/10. Published 2026-02-19.
- How severe is CVE-2026-26030?
- Critical severity. CVSS v3 base score is 9.9 out of 10.
- Is CVE-2026-26030 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.