# CVE-2026-100354: kin-openapi: Uncontrolled Recursion on Circular allOf/anyOf/oneOf Schemas Causes Fatal Process Crash

> Attackers can crash the application by sending requests with circular schema references, causing uncontrolled recursion and stack overflow.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 Oct 2026
- **Updated:** 15 Oct 2026
- **Also known as:** CLEANSTART-2026-OD40775, DEBIAN-CVE-2026-100354, ECHO-8733-0860-28e1, GHSA-g8cf-rcjf-c8cf, MINI-27qg-968w-vcrf, MINI-2qr7-mc8f-56c9, MINI-337m-6g9f-q2vj, MINI-445q-hv9r-2q52, MINI-59cp-xphp-hq7w, MINI-643m-3rr7-33cr, MINI-87vh-x2fj-f6h9, MINI-8h9w-5mvq-mhfc, MINI-9pr6-38fw-rwj4, MINI-9pv3-p9rh-rfq4, MINI-c8wg-hr79-8c5h, MINI-cq56-j9vg-9mrp, MINI-fwg9-wh24-vqf5, MINI-g7g9-8j9q-qc7q, MINI-gcpg-r879-683j, MINI-gr94-fgvw-77h3, MINI-m665-chjq-j4jf, MINI-q5f8-mww4-7mp2, MINI-rc6m-4c9v-55wh, MINI-rv79-8qj2-x5c4, MINI-v87c-wxfm-8wgv, MINI-vf3f-c4wh-r6jm, MINI-w77v-9hg6-w7mp, MINI-whhq-rmcx-5282, MINI-xqx8-qh72-5fg8, MINI-xx6p-j2q8-rjm2, UBUNTU-CVE-2026-100354

## What is CVE-2026-100354?

CVE-2026-100354 is a high-severity denial of service vulnerability in getkin kin-openapi, published on 15 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

kin-openapi is a Go project for handling OpenAPI files. Prior to 0.149.0, runtime request, response, and direct schema validation lacks cycle detection when an allOf, anyOf, or oneOf chain refers back to an ancestor schema, even though loading and document validation accept the circular reference. A request or response that reaches the affected schema causes unbounded recursion in Schema.visitJSON or openapi3filter.decodeValue and exhausts the Go goroutine stack. The resulting fatal stack overflow cannot be caught with recover and terminates the entire process, including unrelated requests. This issue is fixed in version 0.149.0.

Weakness: CWE-674 (Uncontrolled Recursion)

## Which versions are affected by CVE-2026-100354?

2 open source packages ship an affected version, including github.com/getkin/kin-openapi.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/getkin/kin-openapi` | Go | All versions | 0.149.0 |
| `github.com/getkin/kin-openapi` | Go | All versions | 0.149.0 |

## How do I fix CVE-2026-100354?

Upgrade github.com/getkin/kin-openapi to 0.149.0 or later.

## Is CVE-2026-100354 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-100354 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-100354 and fix it if it is affected.

What it is: CVE-2026-100354 is a high-severity denial of service vulnerability in getkin kin-openapi, published on 15 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-100354 exists.

Affected packages and fixed versions:
- github.com/getkin/kin-openapi (Go): affected all versions; fixed in 0.149.0
- github.com/getkin/kin-openapi (Go): affected all versions; fixed in 0.149.0

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-2026-100354/ (Markdown: https://insights.sbomify.com/CVE-2026-100354/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-100354
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-100354
- OSV: https://osv.dev/vulnerability/CVE-2026-100354

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-100354/
Summaries are generated and may contain mistakes; the official description above is the record.