#VU83516 Information disclosure in ZyXEL Communications Corp. products - CVE-2023-35136

Vulnerability identifier: #VU83516

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2023-35136

CWE-ID: CWE-200

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
ATP series
Hardware solutions / Routers for home users
USG FLEX series
Client/Desktop applications / Antivirus software/Personal firewalls
VPN series
Client/Desktop applications / Antivirus software/Personal firewalls
USG FLEX 50W
Hardware solutions / Firmware
USG20W-VPN
Hardware solutions / Firmware

Vendor: ZyXEL Communications Corp.

Description

The vulnerability allows a local user to gain access to potentially sensitive information.

The vulnerability exists due to improper input validation in the "Quagga" package. A local user can gain unauthorized access to configuration files on the target device.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

ATP series: 4.32 - 5.37

USG FLEX series: 4.50 - 5.37

USG FLEX 50W: 4.16 - 5.37

USG20W-VPN: 4.16 - 5.37

VPN series: 4.30 - 5.37

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External links
https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-aps

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.