CVE-2026-41134
CVE-2026-41134 is a remote code execution vulnerability in kiota. O3 Security confirms whether CVE-2026-41134 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Kiota: Code Generation Literal Injection
Blast Radius
kiota.NETMicrosoft.OpenApi.Kiota.NETMicrosoft.OpenApi.Kiota.BuilderReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.
Description
Kiota is an OpenAPI based HTTP Client code generator. Versions prior to 1.31.1 are affected by a code-generation literal injection vulnerability in multiple writer sinks (for example: serialization/deserialization keys, path/query parameter mappings, URL template metadata, enum/property metadata, and default value emission). When malicious values from an OpenAPI description are emitted into generated source without context-appropriate escaping, an attacker can break out of string literals and inject additional code into generated clients. This issue is only practically exploitable when the OpenAPI description used for generation is from an untrusted source, or a normally trusted OpenAPI description has been compromised/tampered with. Only generating from trusted, integrity-protected API descriptions significantly reduces the risk. To remediate the issue, upgrade Kiota to 1.31.1 or later and regenerate/refresh existing generated clients as a precaution. Refreshing generated clients ensures previously generated vulnerable code is replaced with hardened output.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| .NETNuGet | kiota | all versions | 1.31.1 |
| .NETNuGet | Microsoft.OpenApi.Kiota | all versions | 1.31.1 |
| .NETNuGet | Microsoft.OpenApi.Kiota.Builder | all versions | 1.31.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for kiota. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update kiota to 1.31.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-41134 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-41134 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-41134. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-41134 in your dependencies?
O3 detects CVE-2026-41134 across NuGet dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.