Linux Kernel up to 4.7.3 Filesystem fs/crypto/policy.c fscrypt_process_policy access control

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

A vulnerability has been found in Linux Kernel up to 4.7.3 (Operating System) and classified as problematic. Affected by this vulnerability is the function fscrypt_process_policy of the file fs/crypto/policy.c of the component Filesystem Handler. The manipulation with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-264. As an impact it is known to affect availability. The summary by CVE is:

A missing authorization check in the fscrypt_process_policy function in fs/crypto/policy.c in the ext4 and f2fs filesystem encryption support in the Linux kernel before 4.7.4 allows a user to assign an encryption policy to a directory owned by a different user, potentially creating a denial of service.

The bug was discovered 09/02/2016. The weakness was presented 04/04/2017 as confirmed git commit (GIT Repository). It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2016-10318 since 04/04/2017. The attack can be launched remotely. A single authentication is required for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

The vulnerability was handled as a non-public zero-day exploit for at least 214 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 100044 (openSUSE Security Update : the Linux Kernel (openSUSE-2017-562)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family SuSE Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 157613 (Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel (ELSA-2017-3659)).

Upgrading to version 4.7.4 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be patching the affected component. A possible mitigation has been published 2 months after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (100044) and SecurityFocus (BID 97404†). See VDB-110104 for similar entry. 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: 🔍
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CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
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CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Access control
CWE: CWE-264
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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EPSS Percentile: 🔍

Price Prediction: 🔍
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Nessus ID: 100044
Nessus Name: openSUSE Security Update : the Linux Kernel (openSUSE-2017-562)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 850584
OpenVAS Name: SuSE Update for Linux Kernel openSUSE-SU-2017:1215-1 (Linux Kernel)
OpenVAS File: 🔍
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Qualys ID: 🔍
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Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
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Upgrade: Kernel 4.7.4
Patch: git.kernel.org

Timelineinfo

09/02/2016 🔍
04/04/2017 +214 days 🔍
04/04/2017 +0 days 🔍
04/04/2017 +0 days 🔍
04/04/2017 +0 days 🔍
04/04/2017 +0 days 🔍
05/08/2017 +34 days 🔍
05/09/2017 +1 days 🔍
11/27/2022 +2028 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: 163ae1c6ad6299b19e22b4a35d5ab24a89791a98
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2016-10318 (🔍)
GCVE (CVE): GCVE-0-2016-10318
GCVE (VulDB): GCVE-100-99283
SecurityFocus: 97404 - Linux Kernel CVE-2016-10318 Denial of Service Vulnerability
OSVDB: - CVE-2016-10318 - Linux - Denial of Service Issue

See also: 🔍

Entryinfo

Created: 04/04/2017 10:24 PM
Updated: 11/27/2022 07:28 AM
Changes: 04/04/2017 10:24 PM (89), 11/27/2022 07:28 AM (4)
Complete: 🔍
Cache ID: 18:6FF:40

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