CVE-2023-6340: netextender Stack Overflow — Fix

Description

SonicWall Capture Client version 3.7.10, NetExtender client version 10.2.337 and earlier versions are installed with sfpmonitor.sys driver. The driver has been found to be vulnerable to Denial-of-Service (DoS) caused by Stack-based Buffer Overflow vulnerability.

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-121 CWE-121

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
sonicwall	capture_client	< 3.7.10
sonicwall	netextender	< 10.2.337

References

Advisories & Patches

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2023-0019 https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2023-0019

Frequently Asked Questions

What is CVE-2023-6340? +

SonicWall Capture Client version 3.7.10, NetExtender client version 10.2.337 and earlier versions are installed with sfpmonitor.sys driver. The driver has been found to be vulnerable to Denial-of-Service (DoS) caused by Stack-based Buffer Overflow vulnerability. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2023-6340? +

CVE-2023-6340 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2023-6340? +

CVE-2023-6340 affects products from sonicwall, specifically: capture_client, netextender. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-6340? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2023-6340