Zyxel ATP/USG FLEX/VPN up to 5.35 Configuration Parser denial of service

Summaryinfo

A vulnerability identified as problematic has been detected in Zyxel ATP, USG FLEX and VPN up to 5.35. This impacts an unknown function of the component Configuration Parser. Performing a manipulation results in denial of service. This vulnerability was named CVE-2023-22916. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability classified as problematic has been found in Zyxel ATP, USG FLEX and VPN up to 5.35 (Network Encryption Software). This affects some unknown functionality of the component Configuration Parser. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on integrity, and availability. The summary by CVE is:

The configuration parser of Zyxel ATP series firmware versions 5.10 through 5.35, USG FLEX series firmware versions 5.00 through 5.35, USG FLEX 50(W) firmware versions 5.10 through 5.35, USG20(W)-VPN firmware versions 5.10 through 5.35, and VPN series firmware versions 5.00 through 5.35, which fails to properly sanitize user input. A remote unauthenticated attacker could leverage the vulnerability to modify device configuration data, resulting in DoS conditions on an affected device if the attacker could trick an authorized administrator to switch the management mode to the cloud mode.

The weakness was presented 04/24/2023. The advisory is shared at zyxel.com. This vulnerability is uniquely identified as CVE-2023-22916 since 01/10/2023. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly 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-2023-27018). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Network Encryption Software

Vendor

• Zyxel

Name

• ATP
• 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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