---
title: "CVE-2009-4128\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-2009-4128?format=md
keywords: index, follow
---

# CVE-2009-4128

Publication date 1 December 2009

Last updated 24 July 2024

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Ubuntu priority

**Medium**

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

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## Description

GNU GRand Unified Bootloader (GRUB) 2 1.97 only compares the submitted
portion of a password with the actual password, which makes it easier for
physically proximate attackers to conduct brute force attacks and bypass
authentication by submitting a password whose length is 1.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2009-4128?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| grub2 | 9.10 karmic | Fixed 1.97~beta4-1ubuntu4.1 |
| 9.04 jaunty | Not affected |
| 8.10 intrepid | Not affected |
| 8.04 LTS hardy | Not affected |
| 6.06 LTS dapper | Not affected |

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* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## Notes

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### [mdeslaur](https://launchpad.net/~mdeslaur)

grub2 only

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-4128)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2009-4128)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2009-4128)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2009-4128)

### Related Ubuntu Security Notices (USN)

+ [USN-868-1](https://usn.ubuntu.com/USN-868-1)
+ GRUB 2 vulnerability
+ 9 December 2009

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2009-4128>