Linux Kernel TUN Device Driver drivers/net/tun.c tun_napi_alloc_frags out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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7.6$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Linux Kernel. Impacted is the function tun_napi_alloc_frags of the file drivers/net/tun.c of the component TUN Device Driver Handler. The manipulation leads to out-of-bounds. This vulnerability is traded as CVE-2023-3812. An attack has to be approached locally. There is no exploit available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability was found in Linux Kernel (Operating System) (affected version unknown) and classified as critical. This issue affects the function tun_napi_alloc_frags of the file drivers/net/tun.c of the component TUN Device Driver Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

An out-of-bounds memory access flaw was found in the Linux kernel’s TUN/TAP device driver functionality in how a user generates a malicious (too big) networking packet when napi frags is enabled. This flaw allows a local user to crash or potentially escalate their privileges on the system.

The weakness was shared 07/24/2023. The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2023-3812 since 07/20/2023. Technical details are known, but no exploit is available.

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

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-44445). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.6

VulDB Base Score: 7.8
VulDB Temp Score: 7.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 7.8
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

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

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
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: Patch
Status: 🔍

0-Day Time: 🔍

Patch: git.kernel.org

Timelineinfo

07/20/2023 🔍
07/24/2023 +4 days 🔍
07/24/2023 +0 days 🔍
10/09/2025 +808 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-3812 (🔍)
GCVE (CVE): GCVE-0-2023-3812
GCVE (VulDB): GCVE-100-235229
EUVD: 🔍

Entryinfo

Created: 07/24/2023 18:38
Updated: 10/09/2025 17:02
Changes: 07/24/2023 18:38 (52), 10/09/2025 17:02 (16)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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