CVE-2019-11232 in BiYan
Summary
by MITRE
EXCELLENT INFOTEK BiYan v1.57 ~ v2.8 allows an attacker to leak user information (Password) without being authenticated, by sending an EMP_NO element to the kws_login/asp/query_user.asp URI, and then reading the PWD element.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 10/06/2023
The vulnerability identified as CVE-2019-11232 affects the EXCELLENT INFOTEK BiYan system version 1.57 through 2.8, representing a critical authentication bypass and information disclosure flaw that fundamentally undermines the system's security posture. This vulnerability resides within the kws_login/asp/query_user.asp endpoint, which processes user authentication requests without proper authorization checks. The flaw enables unauthenticated attackers to exploit the system's user query functionality by simply submitting an EMP_NO parameter through the HTTP request, thereby gaining access to sensitive user credentials stored in the PWD element of the response.
The technical implementation of this vulnerability stems from inadequate input validation and authentication mechanisms within the ASP-based web application. When an attacker sends a crafted EMP_NO element to the query_user.asp URI, the system processes the request without verifying whether the requester possesses legitimate credentials or authorization rights. This design flaw directly violates the principle of least privilege and demonstrates a critical failure in access control implementation. The system's failure to validate user authentication status before processing user information queries creates an information disclosure vulnerability that allows attackers to extract password hashes or plain text passwords from the database. This weakness aligns with CWE-287, which addresses improper authentication issues, and represents a classic example of insecure direct object reference vulnerabilities that enable unauthorized access to sensitive data.
The operational impact of this vulnerability extends beyond simple credential theft, as it provides attackers with the foundation for further exploitation and lateral movement within the network. Once an attacker obtains valid user credentials, they can potentially escalate privileges, access additional system resources, or launch targeted attacks against other systems within the organization's infrastructure. The vulnerability's accessibility without authentication makes it particularly dangerous as it requires no prior access or credentials to exploit, enabling even novice attackers to discover and leverage the flaw. This creates a significant risk for organizations using the affected software, as the compromise of user credentials can lead to complete system takeover and data breaches. The vulnerability also violates several ATT&CK framework techniques including T1078 for valid accounts and T1566 for credential harvesting, making it a valuable target for attackers seeking to establish persistent access and maintain control over compromised systems.
Organizations affected by this vulnerability should immediately implement mitigations including input validation controls, authentication enforcement, and access restriction measures to prevent unauthorized access to sensitive user information. The recommended approach involves implementing proper authentication checks before processing any user query requests, sanitizing all input parameters to prevent injection attacks, and restricting access to the vulnerable endpoint through network segmentation and firewall rules. Additionally, organizations should consider implementing web application firewalls to detect and block malicious requests attempting to exploit this vulnerability. The remediation process should include updating to the latest version of the software where the vulnerability has been patched, conducting comprehensive security assessments of similar systems, and implementing proper monitoring and alerting mechanisms to detect unauthorized access attempts. Regular security audits and penetration testing should also be conducted to identify and address similar authentication bypass vulnerabilities that may exist within the organization's broader technology infrastructure.