CVE-2026-76905 is a high-severity (CVSS 7.5) NULL Pointer Dereference vulnerability in github.com/getkin/kin-openapi. O3 Security confirms whether CVE-2026-76905 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
kin-openapi openai3filter: nil-pointer panic in ConvertErrors on malformed multipart/form-data body enables unauthenticated DoS
Real-World Exposure
github.com/getkin/kin-openapiReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/getkin/kin-openapi | ≥ 0.10.0&&< 0.141.0 | 0.141.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/getkin/kin-openapi. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/getkin/kin-openapi to 0.141.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-76905 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-76905 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-76905. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-76905 in your dependencies?
O3 detects CVE-2026-76905 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.