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

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.3	$0-$5k	0.00

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 160041 is related to this item.

Productinfo

Type

Operating System

Vendor

Linux

Name

Kernel

Version

License

open-source

CPE 2.3info

CPE 2.2info

CVSSv4info

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

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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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: 🔍

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	unlock	unlock	unlock	unlock
Today	unlock	unlock	unlock	unlock

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 (🔍)
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: 🔍