CVE-2026-59866

CRITICAL

Kiota: Arbitrary file write + code-injection via x-ms-kiota-info clientClassName and clientNamespaceName

Title source: cna
STIX 2.1

Description

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.

Scores

CVSS v4 9.3
EPSS 0.0135
EPSS Percentile 68.8%
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

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact total

Details

CWE
CWE-22 CWE-94
Status published
Products (3)
microsoft/kiota < 1.32.5
nuget/Microsoft.OpenApi.Kiota 0 - 1.32.5NuGet
nuget/Microsoft.OpenApi.Kiota.Builder 0 - 1.32.5NuGet
Published Jul 16, 2026
Tracked Since Jul 16, 2026