Linux Kernel 2.6.28.2 lookup_cb_cred improper authentication

CVSS Meta Temp Score
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CTI Interest Score
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7.5$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel 2.6.28.2. It has been classified as problematic. This affects the function lookup_cb_cred. The manipulation leads to improper authentication. This vulnerability is uniquely identified as CVE-2009-3623. No exploit exists.

Detailsinfo

A vulnerability was found in Linux Kernel 2.6.28.2 (Operating System) and classified as critical. This issue affects the function lookup_cb_cred. The manipulation with an unknown input leads to a improper authentication vulnerability. Using CWE to declare the problem leads to CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. Impacted is availability. The summary by CVE is:

The lookup_cb_cred function in fs/nfsd/nfs4callback.c in the nfsd4 subsystem in the Linux kernel before 2.6.31.2 attempts to access a credentials cache even when a client specifies the AUTH_NULL authentication flavor, which allows remote attackers to cause a denial of service (NULL pointer dereference and system crash) via an NFSv4 mount request.

The issue has been introduced in 12/25/2008. The weakness was disclosed 10/30/2009 as Bug 530269 as not defined bug report (Bugzilla). The advisory is shared at bugzilla.redhat.com. The identification of this vulnerability is CVE-2009-3623 since 10/09/2009. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 309 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 43026 (Ubuntu 6.06 LTS / 8.04 LTS / 8.10 / 9.04 / 9.10 : linux, linux-source-2.6.15 vulnerabilities (USN-864-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Ubuntu Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 195006 (Ubuntu Security Notification for Linux, Linux-source-2.6.15 Vulnerabilities (USN-864-1)).

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 (54079), Tenable (43026) and Vulnerability Center (SBV-24538†). The entry VDB-50817 is pretty similar. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.5

VulDB Base Score: 7.5
VulDB Temp Score: 7.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 43026
Nessus Name: Ubuntu 6.06 LTS / 8.04 LTS / 8.10 / 9.04 / 9.10 : linux, linux-source-2.6.15 vulnerabilities (USN-864-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

10/02/2006 🔍
12/25/2008 +815 days 🔍
10/09/2009 +288 days 🔍
10/30/2009 +21 days 🔍
10/30/2009 +0 days 🔍
01/11/2010 +73 days 🔍
03/18/2015 +1892 days 🔍
03/27/2025 +3662 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: Bug 530269
Status: Not defined
Confirmation: 🔍

CVE: CVE-2009-3623 (🔍)
GCVE (CVE): GCVE-0-2009-3623
GCVE (VulDB): GCVE-100-50657

OVAL: 🔍

X-Force: 54079
Vulnerability Center: 24538 - Linux kernel \x3C 2.6.31.2 Vulnerability Allows Local Attackers to Cause DoS via NFSv4 Mount Request, Medium

See also: 🔍

Entryinfo

Created: 03/18/2015 15:15
Updated: 03/27/2025 08:12
Changes: 03/18/2015 15:15 (54), 02/19/2017 21:42 (11), 08/24/2021 23:21 (3), 03/27/2025 08:12 (16)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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