CVE-2026-26030Public exploitNetwork attack vector

Code execution via evaluated vector-store filters

Published Feb 19, 2026 · Updated Feb 19, 2026

Code injection in Microsoft Semantic Kernel before 1.39.4 allows remote authenticated users to execute code through vector-store filters. InMemoryVectorStore's default Search Plugin filter interpolates model-controlled arguments into a Python lambda, then passes it to eval after an incomplete AST blocklist. Exploitation requires a prompt-injection path and the default Search Plugin backed by the in-memory store, enabling commands with the agent host's privileges.

CVSS severity9.9
Critical
EPSS probability3.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Code injection in Microsoft Semantic Kernel before 1.39.4 allows remote authenticated users to execute code through vector-store filters. InMemoryVectorStore's default Search Plugin filter interpolates model-controlled arguments into a Python lambda, then passes it to eval after an incomplete AST blocklist. Exploitation requires a prompt-injection path and the default Search Plugin backed by the in-memory store, enabling commands with the agent host's privileges.

The record

CVE
CVE-2026-26030
Published
Feb 19, 2026
Updated
Feb 19, 2026
Vendor
Microsoft
Product
Semantic Kernel
Classifications
CWE-94, T1059
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.39.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Microsoft · Semantic Kernelversion=< 1.39.4

Published CVSS scores

9.9GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-94Improper Control of Generation of Code ('Code Injection')
T1059Command and Scripting Interpreter

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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