Incorrect Permission Assignment Vulnerability in Zyxel USG FLEX H Series Firmware

CVE-2025-1731

What is CVE-2025-1731?

CVE-2025-1731 is a vulnerability found in the Zyxel USG FLEX H series firmware, specifically within versions 1.20 to 1.31. The firmware is designed to manage security functions for networks, including firewall capabilities and the overall protection of sensitive information. This vulnerability centers on an incorrect permission assignment within PostgreSQL commands, which could allow an authenticated local attacker with minimal privileges to exploit this weakness. If successfully executed, the attacker could gain unauthorized access to the Linux shell, enabling them to execute malicious scripts or alter critical system configurations, provided the administrator remains logged in and the session token is valid. This could lead to significant security breaches in an organization’s network.

Technical Details

The vulnerability resides in the handling of PostgreSQL commands within the firmware of Zyxel's USG FLEX H series devices. The issue allows low-privileged, authenticated local users to escalate their privileges by leveraging token-based access. Attackers can create malicious scripts that take advantage of this flaw, which compromises the device's integrity and security. This unauthorized access hinges on the condition that the network administrator has not logged out, meaning they maintain an active session, allowing the stolen token to provide elevated permissions.

Potential impact of CVE-2025-1731

1. Unauthorized System Access: Attackers could exploit this vulnerability to gain administrator-level access to the network devices, potentially leading to unauthorized control over critical security functions.

2. Modification of Sensitive Configurations: With access to the Linux shell, an attacker could alter system configurations, compromising the firewall and network protection capabilities, thus exposing the organization to various security threats.

3. Increased Risk of Data Breaches: The ability to execute malicious scripts can facilitate further exploitation opportunities, allowing unauthorized access to sensitive data stored within the network. This increases the risk of data breaches and compliance violations.

News Articles

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