CVE-2025-56752 is a critical vulnerability identified in the firmware of Ruijie RG-ES series network switches, specifically in version ESW_1.0(1)B1P39. The flaw allows remote attackers to completely bypass the authentication mechanism by sending a specially crafted HTTP POST request to the /user.cgi endpoint. This bypass effectively grants attackers unrestricted administrative access to the device without requiring valid credentials. With such access, attackers can alter administrative settings, potentially seizing full control of the affected switches. This level of control could enable attackers to manipulate network configurations, disrupt traffic flow, create persistent backdoors, or launch further attacks within the network. The vulnerability arises from improper validation or flawed logic in the authentication process of the web management interface. Although no known exploits are currently reported in the wild, the nature of the vulnerability makes it highly exploitable once discovered. The lack of a CVSS score indicates that the vulnerability is newly published and has not yet undergone formal severity assessment. The affected firmware version is explicitly identified, but no information is provided about other versions, suggesting that this specific release is vulnerable. The vulnerability's exploitation requires only network access to the management interface, which is commonly accessible within enterprise environments, increasing the risk of exploitation if the device is exposed or if an attacker gains internal network access.

For European organizations, the impact of this vulnerability could be severe. Ruijie switches are used in various sectors including enterprise, education, and government networks. An attacker exploiting this vulnerability could gain full administrative control over network switches, leading to potential network outages, interception or manipulation of sensitive data, and disruption of critical services. This could compromise confidentiality, integrity, and availability of network communications. Given the central role of network switches in managing traffic, the vulnerability could facilitate lateral movement within corporate networks, enabling attackers to escalate privileges and access other critical systems. The risk is heightened in environments where network management interfaces are not properly segmented or protected. Additionally, the ability to alter administrative settings could allow attackers to disable security controls or install persistent malicious configurations, complicating incident response and recovery efforts. The absence of known exploits currently provides a window for proactive mitigation, but the vulnerability's characteristics suggest that exploitation could be straightforward once a proof-of-concept is developed.

Organizations should immediately identify any Ruijie RG-ES series switches running the vulnerable firmware ESW_1.0(1)B1P39. Since no patch links are currently available, organizations should contact Ruijie Networks for official firmware updates or advisories. In the interim, it is critical to restrict access to the management interface by implementing network segmentation and access control lists (ACLs) to limit management traffic only to trusted administrators and management stations. Disabling HTTP management access in favor of more secure protocols such as HTTPS or SSH, if supported, can reduce exposure. Monitoring network traffic for unusual POST requests to /user.cgi and implementing intrusion detection/prevention systems (IDS/IPS) with custom signatures can help detect exploitation attempts. Regularly auditing device configurations and logs for unauthorized changes is also recommended. Organizations should prepare incident response plans specifically addressing network device compromise and ensure backups of device configurations are maintained securely. Finally, educating network administrators about this vulnerability and enforcing strong operational security practices around network device management will reduce risk.