CVE-2026-59862Network attack vector

Arbitrary code execution via Python comment breakout

Published Jul 16, 2026 · Updated Jul 16, 2026

Code injection in the Python generator for Microsoft Kiota allows attackers to execute arbitrary code through malicious OpenAPI specifications. KiotaBuilder.SetEnumOptions passes x-ms-enum.values[].description into Documentation.DescriptionTemplate, while PythonConventionService.RemoveInvalidDescriptionCharacters leaves newlines intact, letting generated comments split into module-scope statements. Execution requires generating a Python client from the malicious specification and importing the generated module.

CVSS severity7.5
High
EPSS probability1.38%
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 the Python generator for Microsoft Kiota allows attackers to execute arbitrary code through malicious OpenAPI specifications. KiotaBuilder.SetEnumOptions passes x-ms-enum.values[].description into Documentation.DescriptionTemplate, while PythonConventionService.RemoveInvalidDescriptionCharacters leaves newlines intact, letting generated comments split into module-scope statements. Execution requires generating a Python client from the malicious specification and importing the generated module.

The record

CVE
CVE-2026-59862
Published
Jul 16, 2026
Updated
Jul 16, 2026
Vendor
Microsoft
Product
Kiota
Classifications
CWE-94, T1059.006
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 16, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 16, 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=< 1.32.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Microsoft · Kiotaversion=< 1.32.0

Published CVSS scores

7.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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.

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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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-94Improper Control of Generation of Code ('Code Injection')
T1059.006Command and Scripting Interpreter: Python

Public exploit references

No public exploit references are available in this record.

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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