GNU Grub 2 1.97 improper authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability was found in GNU Grub 2 1.97. It has been classified as critical. This affects some unknown processing. The manipulation with an unknown input leads to a improper authentication vulnerability. CWE is classifying the issue as CWE-287. When an actor claims to have a given identity, the software does not prove or insufficiently proves that the claim is correct. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was presented 12/01/2009 (Website). The advisory is shared at This vulnerability is uniquely identified as CVE-2009-4128 since 11/30/2009. The exploitability is told to be easy. An attack has to be approached locally. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 65119 (Ubuntu 9.10 : grub2 vulnerability (USN-868-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Ubuntu Local Security Checks.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at X-Force (54210) and Tenable (65119).





  • open-source

CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 8.4
VulDB Meta Temp Score: 8.4

VulDB Base Score: 8.4
VulDB Temp Score: 8.4
VulDB Vector: 🔍
VulDB Reliability: 🔍



VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍


Class: Improper authentication
CWE: CWE-287
ATT&CK: Unknown

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Nessus ID: 65119
Nessus Name: Ubuntu 9.10 : grub2 vulnerability (USN-868-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Port: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍


10/02/2006 🔍
11/08/2009 +1133 days 🔍
11/30/2009 +22 days 🔍
12/01/2009 +1 days 🔍
12/01/2009 +0 days 🔍
01/11/2010 +41 days 🔍
03/09/2013 +1153 days 🔍
03/18/2015 +739 days 🔍
08/28/2021 +2355 days 🔍



Status: Not defined
Confirmation: 🔍

CVE: CVE-2009-4128 (🔍)

X-Force: 54210
Vulnerability Center: 24537 - GNU GRand Unified Bootloader (GRUB) 1.97 Local Authentication Bypass Vulnerability, Medium
SecurityFocus: 36968 - GNU GRUB Local Authentication Bypass Vulnerability


Created: 03/18/2015 03:15 PM
Updated: 08/28/2021 09:49 AM
Changes: 03/18/2015 03:15 PM (52), 02/19/2017 08:00 PM (12), 08/28/2021 09:49 AM (3)
Complete: 🔍


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