CVE-2021-21429
LOWCreation of Temporary File in Directory with Insecure Permissions in the OpenAPI Generator Maven plugin
Blast Radius
org.openapitools:openapi-generator-maven-pluginReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
OpenAPI Generator allows generation of API client libraries, server stubs, documentation and configuration automatically given an OpenAPI Spec. Using File.createTempFile in JDK will result in creating and using insecure temporary files that can leave application and system data vulnerable to attacks. OpenAPI Generator maven plug-in creates insecure temporary files during the process. The issue has been patched with Files.createTempFile and released in the v5.1.0 stable version.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.openapitools:openapi-generator-maven-plugin | all versions | 5.1.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.openapitools:openapi-generator-maven-plugin. 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 org.openapitools:openapi-generator-maven-plugin to 5.1.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-21429 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-2021-21429 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-2021-21429. 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-2021-21429 in your dependencies?
O3 detects CVE-2021-21429 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.