CVE-2026-41134 Kiota: Code Generation Literal Injection
Attackers can inject malicious code into generated clients via untrusted OpenAPI descriptions, requiring developers to upgrade Kiota and regenerate clients.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-41134?
CVE-2026-41134 is a high-severity code injection vulnerability in microsoft kiota, published on 22 Apr 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
Kiota is an OpenAPI based HTTP Client code generator. Versions prior to 1.29.1 and 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 1.29.1, 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.
Weakness: CWE-94
Which versions are affected by CVE-2026-41134?
8 open source packages ship an affected version, including Microsoft.OpenApi.Kiota and Microsoft.OpenApi.Kiota.Builder. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
Microsoft.OpenApi.Kiota NuGet | All versions | 1.29.1 |
Microsoft.OpenApi.Kiota NuGet | All versions | 1.29.1 |
Microsoft.OpenApi.Kiota NuGet | From 1.30.0 | 1.31.1 |
Microsoft.OpenApi.Kiota NuGet | From 1.30.0 | 1.31.1 |
Microsoft.OpenApi.Kiota.Builder NuGet | All versions | 1.29.1 |
Microsoft.OpenApi.Kiota.Builder NuGet | All versions | 1.29.1 |
2 more packages
Microsoft.OpenApi.Kiota.Builder NuGet | From 1.30.0 | 1.31.1 |
Microsoft.OpenApi.Kiota.Builder NuGet | From 1.30.0 | 1.31.1 |
Products include Microsoft Kiota.
How do I fix CVE-2026-41134?
Upgrade Microsoft.OpenApi.Kiota to a fixed version for your release line: 1.29.1 or 1.31.1.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-41134 being exploited?
There is no known exploitation of CVE-2026-41134 in the wild and no public exploit code.
Sources
Also known as GHSA-2hx3-vp6r-mg3f.