Zyxel USG FLEX/VPN up to 5.35 account_print.cgi path traversal

Summaryinfo

A vulnerability was found in Zyxel USG FLEX and VPN up to 5.35. It has been rated as critical. The impacted element is an unknown function of the file account_print.cgi. This manipulation causes path traversal. This vulnerability is handled as CVE-2023-22914. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Zyxel USG FLEX and VPN up to 5.35 (Network Encryption Software). It has been declared as critical. Affected by this vulnerability is an unknown function of the file account_print.cgi. The manipulation with an unknown input leads to a path traversal vulnerability. The CWE definition for the vulnerability is CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A path traversal vulnerability in the “account_print.cgi” CGI program of Zyxel USG FLEX series firmware versions 4.50 through 5.35, and VPN series firmware versions 4.30 through 5.35, which could allow a remote authenticated attacker with administrator privileges to execute unauthorized OS commands in the “tmp” directory by uploading a crafted file if the hotspot function were enabled.

The weakness was released 04/24/2023. It is possible to read the advisory at zyxel.com. This vulnerability is known as CVE-2023-22914 since 01/10/2023. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/05/2025). The attack technique deployed by this issue is T1006 according to MITRE ATT&CK.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-27016). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Network Encryption Software

Vendor

• Zyxel

Name

• USG FLEX
• VPN

Version

• 5.0
• 5.1
• 5.2
• 5.3
• 5.4
• 5.5
• 5.6
• 5.7
• 5.8
• 5.9
• 5.10
• 5.11
• 5.12
• 5.13
• 5.14
• 5.15
• 5.16
• 5.17
• 5.18
• 5.19
• 5.20
• 5.21
• 5.22
• 5.23
• 5.24
• 5.25
• 5.26
• 5.27
• 5.28
• 5.29
• 5.30
• 5.31
• 5.32
• 5.33
• 5.34
• 5.35

License

• commercial

Website

• Vendor: https://www.zyxel.com/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

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