# PySAML2 XML external entity attack

Advisory record · `GHSA-m269-wj6g-c459`

- **Identifiers:** `GHSA-m269-wj6g-c459` · `CVE-2016-10127` · `PYSEC-2017-67`
- **State:** Confirmed
- **Severity:** CVSS 9.0 Critical
- **Critical:** Yes: CVSS 9+
- **Weakness (CWE):** [CWE-611](https://cwe.mitre.org/data/definitions/611.html)
- **Tags:** [XML external entities (XXE)](https://agentprime.io/advisories/tag/xxe.md)
- **Published:** 17 May 2022
- **Updated:** 24 Oct 2024
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 17 May 2022, 02:56 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Critical

Critical, because:

- CVSS score 9.0: 9.0 or more.

How we decide what’s critical: <https://agentprime.io/advisories/critical.md>

## Affected packages

- `pysaml2` (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

- 9.0 Critical, CVSS 3.0: `CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H`, from GitHub Advisory Database

- **CISA KEV:** Not listed.
- **EPSS:** 0.026, the 85th 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 17 May 2022. New records show when each source confirmed them.

## Sources

- [GitHub Advisory Database: GHSA-m269-wj6g-c459](https://github.com/advisories/GHSA-m269-wj6g-c459)
- [OSV: GHSA-m269-wj6g-c459](https://osv.dev/vulnerability/GHSA-m269-wj6g-c459)
- <https://nvd.nist.gov/vuln/detail/CVE-2016-10127>
- <https://github.com/rohe/pysaml2/issues/366>
- <https://github.com/rohe/pysaml2/pull/379>
- <https://github.com/rohe/pysaml2/commit/6e09a25d9b4b7aa7a506853210a9a14100b8bc9b>
- <https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=850716>
- <https://github.com/advisories/GHSA-m269-wj6g-c459>
- <https://github.com/pypa/advisory-database/tree/main/vulns/pysaml2/PYSEC-2017-67.yaml>
- <https://github.com/rohe/pysaml2>
- <https://web.archive.org/web/20200227195127/http://www.securityfocus.com/bid/95376>
- <http://www.openwall.com/lists/oss-security/2017/01/19/5>

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-m269-wj6g-c459>, 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-m269-wj6g-c459/>. Everything for agents: <https://agentprime.io/llms.txt>.