---
title: "CVE-2009-4021\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2009-4021?format=md
keywords: index, follow
---

# CVE-2009-4021

Publication date 25 November 2009

Last updated 24 July 2024

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

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## Description

The fuse\_direct\_io function in fs/fuse/file.c in the fuse subsystem in the
Linux kernel before 2.6.32-rc7 might allow attackers to cause a denial of
service (invalid pointer dereference and OOPS) via vectors possibly related
to a memory-consumption attack.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| linux | 9.10 karmic | Not affected |
| 9.04 jaunty | Fixed 2.6.28-18.59 |
| 8.10 intrepid | Fixed 2.6.27-17.45 |
| 8.04 LTS hardy | Fixed 2.6.24-27.65 |
| 6.06 LTS dapper | Not in release |
| linux-source-2.6.15 | 9.10 karmic | Not in release |
| 9.04 jaunty | Not in release |
| 8.10 intrepid | Not in release |
| 8.04 LTS hardy | Not in release |
| 6.06 LTS dapper | Fixed 2.6.15-55.82 |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2009-4021?format=md#patch-details)

### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| linux | * Upstream:   <http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=f60311d5f7670d9539b424e4ed8b5c0872fc9e83> |

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-4021)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2009-4021)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2009-4021)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2009-4021)

### Related Ubuntu Security Notices (USN)

+ [USN-894-1](https://usn.ubuntu.com/USN-894-1)
+ Linux kernel vulnerabilities
+ 5 February 2010

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2009-4021>