### Summary
Microsoft Kiota honors a poisoned `.kiota/workspace.json` — the workspace configuration that Kiota's
documented team workflow has developers commit to their repository — **unvalidated** on
`kiota client generate` / `kiota plugin generate`. A repository (or pull request) containing a malicious
per-client / per-plugin `outputPath` causes Kiota, when a developer or CI runs the documented regenerate
command, to **(CWE-22) write the entire generated client to an arbitrary path outside the workspace** — the
`outputPath` was not confined to the workspace root and absolute paths were accepted.
Confirmed on Kiota **1.32.4** (`KIOTA_CONFIG_PREVIEW=true`, the self-contained `linux-x64` release binary).
### Details
```jsonc
// .kiota/workspace.json (committed to the repo)
"clients": { "MyClient": {
"outputPath": "/abs/path/outside/repo/pwned_client" // -> generated client written here (CWE-22)
}}
```
Running `kiota client generate --client-name MyClient` in the repo writes `MyClient.cs`,
`P/PRequestBuilder.cs`, … to the attacker-chosen `outputPath` (verified outside the working tree).
#### Note on `descriptionLocation`
The per-consumer `descriptionLocation` is intentionally fetched at generation time — this is how Kiota knows
where to pull an updated description from when refreshing a client, the same way any other value in a
committed lock/config file is honored. It is **not** treated as a vulnerability and is unchanged; only
`outputPath` is now confined.
### Impact
A malicious or compromised repository — or a malicious PR that edits `.kiota/workspace.json` — leads to
arbitrary file write on the developer's or CI host's filesystem (overwrite source/build files, drop files in
auto-loaded locations) whenever a teammate clones/pulls and runs the documented `kiota client generate` /
`kiota plugin generate` to refresh the client. CWE-22.
This is a different trust boundary from the OpenAPI-description-based findings: the malicious input is the
Kiota **config**, not the spec.
### Patches
Fixed in **1.29.1 and 1.32.5** (https://github.com/microsoft/kiota/pull/7885). On loading a workspace configuration,
each client/plugin `outputPath` is validated to be a relative subdirectory of the workspace: null/empty,
rooted paths (POSIX `/`, UNC `\\` / `//`, Windows drive `X:\`), and any `..` traversal segment are rejected,
and the resolved full path must stay under the workspace root. Generation aborts with an error if any
consumer's `outputPath` escapes the workspace.
### Remediation
Upgrade to Kiota **1.29.1, 1.32.5** or later. Review any committed workspace configs for `outputPath` values that
point outside the workspace.
- Source published
- 24 Jul 2026 16:11:24 UTC
- Source modified
- 17 Aug 2026 15:00:08 UTC
- Observed here
- 23 Oct 2026 16:01:25 UTC
- Source terms
- GitHub Advisory Database · CC-BY-4.0
Original source record · Cite this exact observation · Complete original publisher JSON
This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.
CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N
Publisher rating · HIGH