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

Advisory record · `GHSA-867q-77cc-98mv`

- **Identifiers:** `GHSA-867q-77cc-98mv` · `CVE-2021-21429`
- **State:** Confirmed
- **Severity:** CVSS 4.0 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-377](https://cwe.mitre.org/data/definitions/377.html) · [CWE-378](https://cwe.mitre.org/data/definitions/378.html) · [CWE-379](https://cwe.mitre.org/data/definitions/379.html) · [CWE-552](https://cwe.mitre.org/data/definitions/552.html)
- **Tags:** [Information disclosure](https://agentprime.io/advisories/tag/info-disclosure.md) · [CWE-377](https://agentprime.io/advisories/tag/cwe-377.md) · [CWE-378](https://agentprime.io/advisories/tag/cwe-378.md) · [CWE-379](https://agentprime.io/advisories/tag/cwe-379.md)
- **Published:** 29 Apr 2021
- **Updated:** 8 Jul 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 29 Apr 2021, 21:51 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `org.openapitools:openapi-generator-maven-plugin` (Maven): affected `<5.1.0`; fixed in `5.1.0`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> The openapi-generator-maven-plugin, versions before 5.1.0, creates temporary files insecurely during code generation, so the contents of OpenAPI specification files can be read by other local users on unix-like systems with a shared temporary directory. An attacker needs a local account on the affected system, and the impact is disclosure of the specification file contents. Upgrade to version 5.1.0 or later, which uses Files.createTempFile instead.

Written 2 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 4.0 Medium, CVSS 3.1: `CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0030, the 22nd percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:19 UTC: First seen by agentprime
- 31 Oct 2026, 14:19 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-867q-77cc-98mv)

## Sources

- [GitHub Advisory Database: GHSA-867q-77cc-98mv](https://github.com/advisories/GHSA-867q-77cc-98mv)
- [OSV: GHSA-867q-77cc-98mv](https://osv.dev/vulnerability/GHSA-867q-77cc-98mv)
- <https://github.com/OpenAPITools/openapi-generator/security/advisories/GHSA-867q-77cc-98mv>
- <https://nvd.nist.gov/vuln/detail/CVE-2021-21429>
- <https://github.com/OpenAPITools/openapi-generator/pull/8795>
- <https://github.com/OpenAPITools/openapi-generator/blob/06ad7a51eff04393203cfa715e54e1fb59d984fe/modules/openapi-generator-maven-plugin/src/main/java/org/openapitools/codegen/plugin/CodeGenMojo.java#L782-L799>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-867q-77cc-98mv>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-867q-77cc-98mv/>. Everything for agents: <https://agentprime.io/llms.txt>.
