# XML External Entity Injection in PyWPS

Advisory record · `GHSA-p9wf-3xpg-c9g5`

- **Identifiers:** `GHSA-p9wf-3xpg-c9g5` · `CVE-2021-39371` · `PYSEC-2021-121`
- **State:** Confirmed
- **Severity:** CVSS 7.5 High
- **Critical:** No
- **Weakness (CWE):** [CWE-91](https://cwe.mitre.org/data/definitions/91.html) · [CWE-611](https://cwe.mitre.org/data/definitions/611.html)
- **Tags:** [Other injection](https://agentprime.io/advisories/tag/injection.md) · [XML external entities (XXE)](https://agentprime.io/advisories/tag/xxe.md)
- **Published:** 2 Sept 2021
- **Updated:** 24 Oct 2024
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 2 Sept 2021, 17:11 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `pywps` (PyPI): affected `<4.5.0`; fixed in `4.5.0`

## 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

- 7.5 High, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`, from GitHub Advisory Database

- **CISA KEV:** Not listed.
- **EPSS:** 0.015, the 75th percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

This record came from the full history of the GitHub Advisory Database, published 2 Sept 2021. New records show when each source confirmed them.

## Sources

- [GitHub Advisory Database: GHSA-p9wf-3xpg-c9g5](https://github.com/advisories/GHSA-p9wf-3xpg-c9g5)
- [OSV: GHSA-p9wf-3xpg-c9g5](https://osv.dev/vulnerability/GHSA-p9wf-3xpg-c9g5)
- <https://nvd.nist.gov/vuln/detail/CVE-2021-39371>
- <https://github.com/geopython/OWSLib/issues/790>
- <https://github.com/geopython/pywps/pull/616>
- <https://github.com/geopython/pywps/commit/7d6b26a2e931df2feca0b7fb24f4d01610825aee>
- <https://github.com/advisories/GHSA-p9wf-3xpg-c9g5>
- <https://github.com/geopython/pywps>
- <https://github.com/pypa/advisory-database/tree/main/vulns/pywps/PYSEC-2021-121.yaml>
- <https://lists.debian.org/debian-lts-announce/2021/09/msg00001.html>

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-p9wf-3xpg-c9g5>, 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-p9wf-3xpg-c9g5/>. Everything for agents: <https://agentprime.io/llms.txt>.