Linux Kernel up to 5.15 XFS xfs/xfs_ioctl.c xfs_ioc_space buffer size

CVSS Meta Temp Score
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CTI Interest Score
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4.8$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 5.15. Affected is the function xfs_ioc_space of the file xfs/xfs_ioctl.c of the component XFS Handler. Such manipulation leads to buffer size. This vulnerability is referenced as CVE-2021-4155. It is possible to launch the attack remotely. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.15 (Operating System) and classified as critical. Affected by this issue is the function xfs_ioc_space of the file xfs/xfs_ioctl.c of the component XFS Handler. The manipulation with an unknown input leads to a buffer size vulnerability. Using CWE to declare the problem leads to CWE-131. The product does not correctly calculate the size to be used when allocating a buffer, which could lead to a buffer overflow. Impacted is confidentiality. CVE summarizes:

A data leak flaw was found in the way XFS_IOC_ALLOCSP IOCTL in the XFS filesystem allowed for size increase of files with unaligned size. A local attacker could use this flaw to leak data on the XFS filesystem otherwise not accessible to them.

The weakness was published 08/25/2022. The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2021-4155 since 12/22/2021. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 236670 (Alibaba Cloud Linux 3 : 0125: cloud-kernel bugfix, enhancement and (ALINUX3-SA-2022:0125)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.16 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 upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (236670). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.9
VulDB Meta Temp Score: 4.8

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

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Buffer size
CWE: CWE-131 / CWE-120 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 236670
Nessus Name: Alibaba Cloud Linux 3 : 0125: cloud-kernel bugfix, enhancement and (ALINUX3-SA-2022:0125)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 5.16
Patch: git.kernel.org

Timelineinfo

12/22/2021 🔍
08/25/2022 +245 days 🔍
08/25/2022 +0 days 🔍
05/18/2025 +997 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2021-4155 (🔍)
GCVE (CVE): GCVE-0-2021-4155
GCVE (VulDB): GCVE-100-207140

Entryinfo

Created: 08/25/2022 09:17
Updated: 05/18/2025 18:27
Changes: 08/25/2022 09:17 (44), 09/25/2022 16:00 (11), 05/18/2025 18:27 (16)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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