CVE-2022-34993 in A3600R
Summary
by MITRE • 08/04/2022
Totolink A3600R_Firmware V4.1.2cu.5182_B20201102 contains a hard code password for root in /etc/shadow.sample.
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Analysis
by VulDB Data Team • 08/30/2022
The vulnerability identified as CVE-2022-34993 represents a critical security flaw in the Totolink A3600R router firmware version V4.1.2cu.5182_B20201102 where a hardcoded root password is embedded within the /etc/shadow.sample file. This configuration exposes the device to immediate unauthorized access attempts and represents a fundamental failure in secure credential management practices. The presence of hardcoded credentials in firmware images directly violates established security principles and creates an persistent backdoor that remains active across device reboots and firmware updates.
This vulnerability falls under the category of hardcoded credentials as classified by CWE-259 and CWE-798, which specifically addresses the storage of passwords or cryptographic keys in source code or configuration files. The technical implementation flaw occurs when developers embed default administrative credentials directly into firmware components during the development lifecycle, failing to implement proper authentication mechanisms or secure credential provisioning processes. The /etc/shadow.sample file serves as a reference template that contains the hardcoded password, making it easily discoverable by attackers who can then leverage this information to gain root access to the device.
The operational impact of this vulnerability is severe and multifaceted, as it allows attackers to achieve complete administrative control over the affected router without requiring any authentication challenges or password guessing attempts. Once an attacker discovers the hardcoded root password, they can modify network configurations, install malicious firmware, redirect traffic, or establish persistent access points within the network. This vulnerability is particularly dangerous in enterprise environments where routers serve as network gateways, as it provides attackers with a direct path to compromise entire network infrastructures and potentially escalate privileges to other connected systems.
The attack surface for this vulnerability extends beyond simple remote access, as it can be exploited through various attack vectors including network scanning, firmware analysis, and social engineering techniques. Attackers can identify this vulnerability by examining firmware images through reverse engineering processes or by analyzing publicly available information about the specific firmware version. The ATT&CK framework categorizes this as a privilege escalation technique under T1068, where attackers leverage hardcoded credentials to gain elevated system access. Additionally, this vulnerability enables lateral movement within networks as attackers can use the compromised router as a pivot point to access other network segments.
Mitigation strategies for CVE-2022-34993 require immediate firmware updates from the vendor, as the hardcoded password cannot be removed from existing installations without a proper software update. Network administrators should implement network segmentation and access controls to limit the impact of compromised devices, while also monitoring for unauthorized access attempts through network logs and intrusion detection systems. The recommended approach involves replacing the affected firmware with versions that properly implement secure authentication mechanisms and do not contain hardcoded credentials. Organizations should also conduct comprehensive vulnerability assessments of their network infrastructure to identify other devices that may contain similar hardcoded credentials, as this represents a common pattern in embedded device security implementations.