Creation of Temporary File in Directory with Insecure Permissions in the OpenAPI Generator Maven plugin

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

4.0 · CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS

• CVE-2021-21429: 0.30% estimated exploitation activity in the next 30 days; percentile 22.30 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact Using File.createTempFile in JDK will result in creating and using insecure temporary files that can leave application and system data vulnerable to attacks. This vulnerability only impacts unix-like systems where the local system temporary directory is shared between all users. This vulnerability does not impact Windows or modern versions of MacOS. OpenAPI Generator Maven plug-in creates insecure temporary files during the code generation process. It creates insecure temporary files to store the OpenAPI specification files provided by the users and these temporary files can be read by any users in the system. The impact of this vulnerability is information disclosure of the contents of the specification file to other local users. Patches The issue has been patched with Files.createTempFile and released in the v5.1.0 stable version. For more information If you have any questions or comments about this advisory: Open an issue in OpenAPI Generator Github repo Email us at…

Published by the source

29 Apr 2021, 21:51 UTC

Last modified by the source

1 Feb 2023, 05:05 UTC

Source last checked

26 Oct 2026, 16:06 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-867q-77cc-98mv

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# Patch Next advisory brief: CVE-2021-21429

Advisory: Creation of Temporary File in Directory with Insecure Permissions in the OpenAPI Generator Maven plugin
IDs: CVE-2021-21429, GHSA-867q-77cc-98mv
Record: https://patchnext.com/advisories/cve-2021-21429 (revision 1, source checked 26 Oct 2026, 16:06 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.0)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: org.openapitools:openapi-generator-maven-plugin 5.1.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.openapitools:openapi-generator-maven-plugin: affected < 5.1.0; fixed in 5.1.0

## Suggested inspection (read-only)
- Maven org.openapitools:openapi-generator-maven-plugin: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on org.openapitools:openapi-generator-maven-plugin.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-867q-77cc-98mv (GitHub-reviewed advisory GHSA-867q-77cc-98mv lists affected ranges: Maven org.openapitools:openapi-generator-maven-plugin >=0 <5.1.0)

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