CVE-2026-59866
Full vulnerability record from the local CVENow database.
Description
Kiota is an OpenAPI based HTTP Client code generator. Prior to 1.29.1 and 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 1.29.1 and 1.32.5 by GenerationConfiguration.SanitizeClientClassName and SanitizeClientNamespaceName.
Severity
CRITICAL
CVSS score
9.3
(v4.0)
Vulnerability status
Deferred
Source identifier
Published
2026-07-16 16:19:15.493000
Last modified
2026-10-24 20:10:00.137000
View original CVE JSON
{
"id": "CVE-2026-59866",
"sourceIdentifier": "[email protected]",
"published": "2026-07-16T16:19:15.493",
"lastModified": "2026-10-24T20:10:00.137",
"vulnStatus": "Deferred",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Kiota is an OpenAPI based HTTP Client code generator. Prior to 1.29.1 and 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 1.29.1 and 1.32.5 by GenerationConfiguration.SanitizeClientClassName and SanitizeClientNamespaceName."
},
{
"lang": "es",
"value": "Kiota es un generador de código de cliente HTTP basado en OpenAPI. Antes de la versión 1.32.5, Kiota emitía valores x-ms-kiota-info clientClassName y clientNamespaceName sin saneamiento de identificadores o rutas, tanto como nombres de clase o espacio de nombres de cliente generados como componentes de ruta de salida generados, cuando kiota generate se ejecutaba sin -c/--class-name, permitiendo que una descripción OpenAPI controlada por un atacante o comprometida escribiera código fuente generado fuera del directorio de salida -o e inyectara texto arbitrario en las declaraciones de clase o espacio de nombres generadas. Este problema se solucionó en la versión 1.32.5 mediante GenerationConfiguration.SanitizeClientClassName y SanitizeClientNamespaceName."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "microsoft",
"product": "kiota",
"versions": [
{
"version": ">= 1.30.0, < 1.31.1",
"status": "affected"
},
{
"version": "< 1.29.1",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV40": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "4.0",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"baseScore": 9.3,
"baseSeverity": "CRITICAL",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnAvailabilityImpact": "HIGH",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"subAvailabilityImpact": "NONE",
"exploitMaturity": "NOT_DEFINED",
"confidentialityRequirement": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"availabilityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-07-17T03:56:40.596267Z",
"id": "CVE-2026-59866",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-22"
},
{
"lang": "en",
"value": "CWE-94"
}
]
}
],
"references": [
{
"url": "https://github.com/microsoft/kiota/commit/dc812dbbf88ef7edf53a890d36b2f9d1460e947d",
"source": "[email protected]"
},
{
"url": "https://github.com/microsoft/kiota/pull/7884",
"source": "[email protected]"
},
{
"url": "https://github.com/microsoft/kiota/releases/tag/v1.32.5",
"source": "[email protected]"
},
{
"url": "https://github.com/microsoft/kiota/security/advisories/GHSA-4vv7-jj25-4gh6",
"source": "[email protected]"
}
]
}