# CVE-2026-105796: Kiota: Code injection through doc-comment delimiter reformation in Kiota Java and PHP generators

> Attackers can inject malicious code into generated Java or PHP clients via crafted OpenAPI descriptions, leading to code execution in the consuming application.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 6 Oct 2026
- **Updated:** 9 Oct 2026
- **Also known as:** GHSA-rm89-rhwj-9j92

## What is CVE-2026-105796?

CVE-2026-105796 is a high-severity code injection vulnerability in Microsoft.OpenApi.Kiota, published on 6 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Kiota is an OpenAPI based HTTP Client code generator. From 0.5.0 until 1.35.0, Kiota's Java and PHP documentation-comment sanitizers delete block-comment terminators rather than neutralizing them, allowing overlapping characters to reform a terminator and place attacker-controlled OpenAPI text outside a generated documentation comment. The Java sanitizer also removes non-ASCII characters after deleting terminators, which can create a new terminator during normalization. Exploitation requires a developer or build pipeline to generate source from the malicious description and then compile and load the Java output or load the PHP output, after which injected code executes in the consuming application or build environment context. The version range is based on the Java defect and does not assert that PHP generation existed in every affected release. This issue is fixed in version 1.35.0.

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2026-105796?

4 open source packages ship an affected version, including Microsoft.OpenApi.Kiota and Microsoft.OpenApi.Kiota.Builder.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `Microsoft.OpenApi.Kiota` | NuGet | From 0.5.0 | 1.35.0 |
| `Microsoft.OpenApi.Kiota` | NuGet | From 0.5.0 | 1.35.0 |
| `Microsoft.OpenApi.Kiota.Builder` | NuGet | From 0.5.0 | 1.35.0 |
| `Microsoft.OpenApi.Kiota.Builder` | NuGet | From 0.5.0 | 1.35.0 |

## How do I fix CVE-2026-105796?

Upgrade Microsoft.OpenApi.Kiota to 1.35.0 or later.

## Is CVE-2026-105796 being exploited?

There is no known exploitation of CVE-2026-105796 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-105796 and fix it if it is affected.

What it is: CVE-2026-105796 is a high-severity code injection vulnerability in Microsoft.OpenApi.Kiota, published on 6 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-105796 in the wild and no public exploit code.

Affected packages and fixed versions:
- Microsoft.OpenApi.Kiota (NuGet): affected from 0.5.0; fixed in 1.35.0
- Microsoft.OpenApi.Kiota (NuGet): affected from 0.5.0; fixed in 1.35.0
- Microsoft.OpenApi.Kiota.Builder (NuGet): affected from 0.5.0; fixed in 1.35.0
- Microsoft.OpenApi.Kiota.Builder (NuGet): affected from 0.5.0; fixed in 1.35.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-105796/ (Markdown: https://insights.sbomify.com/CVE-2026-105796/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-105796
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-105796
- OSV: https://osv.dev/vulnerability/CVE-2026-105796

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-105796/
Summaries are generated and may contain mistakes; the official description above is the record.