Linux Kernel up to 6.3.7 ksmbd connection.c ksmbd_conn_handler_loop pdu_size out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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6.2$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in Linux Kernel up to 6.3.7. The impacted element is the function ksmbd_conn_handler_loop of the file fs/smb/server/connection.c of the component ksmbd. The manipulation of the argument pdu_size results in out-of-bounds. This vulnerability was named CVE-2023-38431. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel up to 6.3.7 (Operating System). Affected is the function ksmbd_conn_handler_loop of the file fs/smb/server/connection.c of the component ksmbd. The manipulation of the argument pdu_size with an unknown input leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality. CVE summarizes:

An issue was discovered in the Linux kernel before 6.3.8. fs/smb/server/connection.c in ksmbd does not validate the relationship between the NetBIOS header's length field and the SMB header sizes, via pdu_size in ksmbd_conn_handler_loop, leading to an out-of-bounds read.

The weakness was presented 07/18/2023. The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2023-38431 since 07/17/2023. Technical details are known, but there is no available exploit.

Upgrading to version 6.3.8 eliminates this vulnerability. The upgrade is hosted for download at cdn.kernel.org. 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.

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Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.2

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.1
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
CWE: CWE-125 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
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: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 6.3.8
Patch: git.kernel.org

Timelineinfo

07/17/2023 🔍
07/18/2023 +1 days 🔍
07/18/2023 +0 days 🔍
08/06/2023 +19 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-38431 (🔍)
GCVE (CVE): GCVE-0-2023-38431
GCVE (VulDB): GCVE-100-234318

Entryinfo

Created: 07/18/2023 09:41
Updated: 08/06/2023 18:43
Changes: 07/18/2023 09:41 (46), 08/06/2023 18:43 (11)
Complete: 🔍
Cache ID: 216::103

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