CVE-2023-40478: rax30 Stack Overflow — Fix

Description

NETGEAR RAX30 Telnet CLI passwd Stack-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR RAX30 routers. Although authentication is required to exploit this vulnerability, the existing authentication mechanism can be bypassed. The specific flaw exists within the telnet CLI service, which listens on TCP port 23. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-20009.

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CVSS v3.1 Score

6.8

MEDIUM

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

Weakness Type (CWE)

CWE-121 CWE-121

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
netgear	rax30_firmware	< 1.0.10.94
netgear	rax30	All

References

Advisories & Patches

https://kb.netgear.com/000065649/Security-Advisory-for-Post-authentication-Buffer-Overflow-on-the-RAX30-PSV-2023-0002 https://kb.netgear.com/000065649/Security-Advisory-for-Post-authentication-Buffer-Overflow-on-the-RAX30-PSV-2023-0002

Other References

https://www.zerodayinitiative.com/advisories/ZDI-23-1163/ https://www.zerodayinitiative.com/advisories/ZDI-23-1163/

Frequently Asked Questions

What is CVE-2023-40478? +

NETGEAR RAX30 Telnet CLI passwd Stack-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR RAX30 routers. Although authentication is required to exploit this vulnerability, the existing authentication mechanism can be bypassed. The specific flaw exists within the telnet CLI service, which listens on TCP port 23. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-20009. It has a CVSS v3.1 base score of 6.8 (MEDIUM).

How severe is CVE-2023-40478? +

CVE-2023-40478 has a CVSS v3.1 score of 6.8 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-2023-40478? +

CVE-2023-40478 affects products from netgear, specifically: rax30, rax30_firmware. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-40478? +

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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