Linux Kernel IOCTL out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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6.4$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel. Impacted is an unknown function of the component IOCTL Handler. The manipulation leads to out-of-bounds write. This vulnerability is listed as CVE-2021-33656. The attack may be initiated remotely. There is no available exploit. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability was found in Linux Kernel (Operating System) (affected version not known) and classified as critical. This issue affects some unknown functionality of the component IOCTL Handler. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

When setting font with malicous data by ioctl cmd PIO_FONT,kernel will write memory out of bounds.

The weakness was presented 07/19/2022. It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2021-33656 since 05/28/2021. The technical details are unknown and an exploit is not publicly available.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.kernel.org.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Vendor

Name

License

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: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.8
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Yes
Local: Partially
Remote: Yes

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: Patch
Status: 🔍

0-Day Time: 🔍

Patch: git.kernel.org

Timelineinfo

05/28/2021 🔍
07/19/2022 +417 days 🔍
07/19/2022 +0 days 🔍
04/02/2025 +988 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2021-33656 (🔍)
GCVE (CVE): GCVE-0-2021-33656
GCVE (VulDB): GCVE-100-204143

Entryinfo

Created: 07/19/2022 09:34
Updated: 04/02/2025 21:00
Changes: 07/19/2022 09:34 (40), 08/06/2022 10:17 (11), 04/02/2025 21:00 (20)
Complete: 🔍
Cache ID: 216::103

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