Microsoft Kiota up to 1.32.4 Code Generator clientNamespaceName injection

Summaryinfo

A vulnerability was found in Microsoft Kiota up to 1.32.4. It has been classified as critical. Affected by this issue is some unknown functionality of the component Code Generator. Performing a manipulation of the argument clientNamespaceName results in injection. This vulnerability is known as CVE-2026-59866. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in Microsoft Kiota up to 1.32.4. It has been classified as critical. This affects an unknown code block of the component Code Generator. The manipulation of the argument clientNamespaceName with an unknown input leads to a injection vulnerability. CWE is classifying the issue as CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Kiota is an OpenAPI based HTTP Client code generator. Prior to 1.32.5, Kiota emitted x-ms-kiota-info clientClassName and clientNamespaceName values without identifier or path sanitization as both generated client class or namespace names and generated output path components when `kiota generate` ran without -c/--class-name, allowing an attacker-controlled or compromised OpenAPI description to write generated source outside the -o output directory and inject arbitrary text into generated class or namespace declarations. This issue is fixed in version 1.32.5 by GenerationConfiguration.SanitizeClientClassName and SanitizeClientNamespaceName.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-59866 since 07/07/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/16/2026). MITRE ATT&CK project uses the attack technique T1055 for this issue.

Upgrading to version 1.32.5 eliminates this vulnerability.

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Productinfo

Vendor

• Microsoft

Name

• Kiota

Version

• 1.32.0
• 1.32.1
• 1.32.2
• 1.32.3
• 1.32.4

License

• commercial

Website

• Vendor: https://www.microsoft.com/
• Product: https://github.com/microsoft/kiota/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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