CVE-2022-0823 in GS1200
Summary
by MITRE • 06/09/2022
An improper control of interaction frequency vulnerability in Zyxel GS1200 series switches could allow a local attacker to guess the password by using a timing side-channel attack.
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Analysis
by VulDB Data Team • 06/11/2022
The CVE-2022-0823 vulnerability represents a critical weakness in Zyxel GS1200 series network switches that exposes the device to password guessing attacks through timing side-channel exploitation. This vulnerability resides within the switch's authentication mechanism and specifically targets the interaction frequency control during password validation processes. The flaw allows an attacker with local access to systematically determine valid passwords by analyzing timing variations in the authentication response behavior. Such timing discrepancies occur because the switch does not implement constant-time password verification routines, creating measurable differences in response times between correct and incorrect password attempts.
The technical implementation of this vulnerability stems from the switch's failure to maintain consistent processing times regardless of password validity. When a user enters a password, the device's authentication subsystem exhibits different execution times based on how many characters match the correct password, enabling attackers to perform systematic brute force attempts with timing analysis. This particular weakness falls under the CWE-1247 category of improper control of interaction frequency, which specifically addresses issues where systems fail to properly regulate the rate and timing of user interactions. The vulnerability demonstrates a classic timing side-channel attack pattern where the attacker leverages temporal information to infer sensitive data, making it particularly dangerous for network infrastructure devices that handle authentication.
The operational impact of CVE-2022-0823 extends beyond simple password compromise, as it represents a fundamental flaw in the switch's security architecture that could enable full network access and control. Local attackers who can access the device's console or network interface can exploit this vulnerability to gain administrative privileges, potentially leading to complete network compromise. The attack requires only local access to the switch, making it particularly concerning for environments where physical access control is inadequate. This vulnerability aligns with ATT&CK technique T1212 which covers "Exploitation for Credential Access" through timing side-channel attacks, demonstrating how seemingly minor implementation flaws can create significant security risks in network infrastructure devices.
Mitigation strategies for this vulnerability require immediate attention from network administrators, including firmware updates from Zyxel that implement constant-time password verification mechanisms. The recommended approach involves applying the vendor-provided security patches that address the timing side-channel issue by ensuring consistent response times regardless of password correctness. Network segmentation and access control measures should be enhanced to limit local physical access to these devices, while implementing additional authentication controls such as multi-factor authentication where possible. Organizations should also consider monitoring for unusual authentication patterns and implementing intrusion detection systems that can identify potential exploitation attempts. The vulnerability highlights the importance of proper cryptographic implementation practices and adherence to security standards such as those outlined in NIST SP 800-133 for secure password handling and timing attack prevention. Regular security assessments and penetration testing should be conducted to identify similar timing vulnerabilities in other network infrastructure components, as this type of weakness can manifest in various authentication systems throughout enterprise networks.