Linux Kernel 2.6.16.9 befs_follow_link input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.2$0-$5k0.00

A vulnerability classified as critical has been found in Linux Kernel 2.6.16.9 (Operating System). Affected is the function befs_follow_link. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on availability. CVE summarizes:

The befs_follow_link function in fs/befs/linuxvfs.c in the Linux kernel before 3.1-rc3 does not validate the length attribute of long symlinks, which allows local users to cause a denial of service (incorrect pointer dereference and OOPS) by accessing a long symlink on a malformed Be filesystem.

The issue has been introduced in 03/20/2006. The weakness was disclosed 08/29/2011 by Timo Warns (oss-sec). The advisory is shared for download at openwall.com. This vulnerability is traded as CVE-2011-2928. The exploitability is told to be easy. The attack needs to be approached locally. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 11/18/2021).

The vulnerability was handled as a non-public zero-day exploit for at least 1988 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 57111 (SuSE 11.1 Security Update : Linux kernel (SAT Patch Numbers 5219 / 5222 / 5223)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family SuSE Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 165576 (SUSE Enterprise Linux Security Update Linux Kernel (SUSE-SA:2011:041)).

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 (69343) and Tenable (57111). The entry 58396 is pretty similar.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 6.2
VulDB Meta Temp Score: 6.2

VulDB Base Score: 6.2
VulDB Temp Score: 6.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Input validation
CWE: CWE-20
ATT&CK: Unknown

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 57111
Nessus Name: SuSE 11.1 Security Update : Linux kernel (SAT Patch Numbers 5219 / 5222 / 5223)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Port: 🔍

OpenVAS ID: 863571
OpenVAS Name: Fedora Update for kernel FEDORA-2011-12874
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Patch: 338d0f0a6fbc82407864606f5b64b75aeb3c70f2

Timelineinfo

03/20/2006 🔍
07/27/2011 +1954 days 🔍
08/19/2011 +23 days 🔍
08/19/2011 +0 days 🔍
08/29/2011 +10 days 🔍
08/29/2011 +0 days 🔍
10/06/2011 +38 days 🔍
12/13/2011 +68 days 🔍
03/23/2015 +1196 days 🔍
11/18/2021 +2432 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: openwall.com
Researcher: Timo Warns
Status: Not defined
Confirmation: 🔍

CVE: CVE-2011-2928 (🔍)
OVAL: 🔍

X-Force: 69343
Vulnerability Center: 33471 - Linux Kernel before 3.1-rc3 Local Denial of Service Vulnerability, Medium
SecurityFocus: 49256 - Linux Kernel 'fs/befs/linuxvfs.c' Local Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 03/23/2015 16:50
Updated: 11/18/2021 11:28
Changes: 03/23/2015 16:50 (64), 04/03/2017 17:47 (10), 11/18/2021 11:21 (6), 11/18/2021 11:28 (1)
Complete: 🔍

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