Zyxel USG FLEX/VPN up to 5.35 account_operator.cgi denial of service

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Zyxel USG FLEX and VPN up to 5.35. Affected by this issue is some unknown functionality of the file account_operator.cgi. This manipulation causes denial of service. This vulnerability is registered as CVE-2023-22913. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as problematic was found in Zyxel USG FLEX and VPN up to 5.35 (Network Encryption Software). Affected by this vulnerability is an unknown functionality of the file account_operator.cgi. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect integrity, and availability. The summary by CVE is:

A post-authentication command injection vulnerability in the “account_operator.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 to modify device configuration data, resulting in denial-of-service (DoS) conditions on an affected device.

The weakness was published 04/24/2023. The advisory is shared at zyxel.com. This vulnerability is known as CVE-2023-22913 since 01/10/2023. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

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-2023-27015). Several companies clearly confirm that VulDB is the primary source for best 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

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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