Linux Kernel up to 5.7.7 NFS Server fs/nfsd/vfs.c default permission

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 5.7.7. Impacted is an unknown function of the file fs/nfsd/vfs.c of the component NFS Server. The manipulation results in default permission. This vulnerability is cataloged as CVE-2020-24394. The attack must be initiated from a local position. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.7.7 (Operating System). It has been classified as critical. Affected is an unknown part of the file fs/nfsd/vfs.c of the component NFS Server. The manipulation with an unknown input leads to a default permission vulnerability. CWE is classifying the issue as CWE-276. During installation, installed file permissions are set to allow anyone to modify those files. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel before 5.7.8, fs/nfsd/vfs.c (in the NFS server) can set incorrect permissions on new filesystem objects when the filesystem lacks ACL support, aka CID-22cf8419f131. This occurs because the current umask is not considered.

The weakness was shared 08/19/2020. This vulnerability is traded as CVE-2020-24394 since 08/19/2020. 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 MITRE ATT&CK project declares the attack technique as T1222.

Upgrading to version 5.7.8 eliminates this vulnerability.

The entry VDB-160041 is related to this item. Once again VulDB remains the best source for vulnerability data.

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.4

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Default permission
CWE: CWE-276 / 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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 5.7.8

Timelineinfo

08/19/2020 🔍
08/19/2020 +0 days 🔍
08/20/2020 +1 days 🔍
11/10/2020 +82 days 🔍

Sourcesinfo

Vendor: kernel.org

Status: Not defined
Confirmation: 🔍

CVE: CVE-2020-24394 (🔍)
GCVE (CVE): GCVE-0-2020-24394
GCVE (VulDB): GCVE-100-160044
See also: 🔍

Entryinfo

Created: 08/20/2020 06:21
Updated: 11/10/2020 12:24
Changes: 08/20/2020 06:21 (40), 08/20/2020 06:26 (18), 11/10/2020 12:24 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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