Linux Kernel up to 4.5.4 Filesystem Layer fs/namei.c access control

CVSS Meta Temp Score
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 4.5.4. It has been rated as problematic. The affected element is an unknown function of the file fs/namei.c of the component Filesystem Layer. Performing a manipulation results in access control. This vulnerability is reported as CVE-2016-6198. The attack requires a local approach. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as problematic has been found in Linux Kernel up to 4.5.4 (Operating System). This affects an unknown function of the file fs/namei.c of the component Filesystem Layer. The manipulation with an unknown input leads to a access control vulnerability. CWE is classifying the issue as CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. This is going to have an impact on availability. The summary by CVE is:

The filesystem layer in the Linux kernel before 4.5.5 proceeds with post-rename operations after an OverlayFS file is renamed to a self-hardlink, which allows local users to cause a denial of service (system crash) via a rename system call, related to fs/namei.c and fs/open.c.

The weakness was disclosed 08/06/2016 (Website). The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2016-6198 since 07/11/2016. The exploitability is told to be easy. An attack has to be approached locally. The successful exploitation requires a authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1068 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 92658 (OracleVM 3.4 : kernel-uek (OVMSA-2016-0091)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family OracleVM Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 157249 (Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel (ELSA-2016-3596)).

Upgrading to version 4.5.5 eliminates this vulnerability. A possible mitigation has been published before and not just after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (92658) and SecurityFocus (BID 91709†). The entry VDB-90656 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: 5.5
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 92658
Nessus Name: OracleVM 3.4 : kernel-uek (OVMSA-2016-0091)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 863279
OpenVAS Name: RedHat Update for kernel RHSA-2016:2574-02
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 4.5.5
Patch: git.kernel.org

Timelineinfo

07/11/2016 🔍
07/11/2016 +0 days 🔍
07/29/2016 +18 days 🔍
08/01/2016 +3 days 🔍
08/06/2016 +5 days 🔍
08/06/2016 +0 days 🔍
08/08/2016 +2 days 🔍
09/13/2022 +2227 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: 54d5ca871e72f2bb172ec9323497f01cd5091ec7
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-6198 (🔍)
GCVE (CVE): GCVE-0-2016-6198
GCVE (VulDB): GCVE-100-90657
SecurityFocus: 91709 - Linux Kernel Multiple Denial of Service Vulnerabilities
SecurityTracker: 1036273

See also: 🔍

Entryinfo

Created: 08/08/2016 15:27
Updated: 09/13/2022 10:20
Changes: 08/08/2016 15:27 (67), 03/22/2019 10:21 (13), 09/13/2022 10:13 (6), 09/13/2022 10:20 (1)
Complete: 🔍
Cache ID: 216:3A8:103

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

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