CVE-2025-65380 identifies a SQL Injection vulnerability in PHPGurukul Billing System version 1.0, located in the admin/index.php endpoint. The root cause is the lack of input validation on the username parameter, which is directly concatenated into an SQL query string. This classic SQL Injection (CWE-89) flaw allows an unauthenticated remote attacker to inject arbitrary SQL commands by manipulating the username parameter in HTTP requests. The vulnerability does not require any privileges or user interaction, making it easier to exploit remotely over the network. Successful exploitation can lead to unauthorized disclosure of sensitive information stored in the backend database and potential modification of data integrity, though it does not impact system availability. The CVSS v3.1 score of 6.5 reflects a medium severity, with attack vector as network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), and impacts on confidentiality and integrity (C:L/I:L) but not availability (A:N). No patches or fixes have been published yet, and no known exploits have been reported in the wild, indicating the vulnerability is newly disclosed. The vulnerability affects all deployments of PHPGurukul Billing System 1.0 where the vulnerable endpoint is exposed, especially in administrative interfaces accessible over the internet or intranet.

For European organizations using PHPGurukul Billing System 1.0, this vulnerability poses a risk of unauthorized data access and potential data manipulation. Confidential customer billing information, payment details, and administrative credentials could be exposed or altered, leading to privacy breaches and financial fraud. The integrity of billing records may be compromised, affecting business operations and compliance with data protection regulations such as GDPR. Although availability is not impacted, the loss of confidentiality and integrity can damage organizational reputation and result in regulatory penalties. Organizations in sectors with high reliance on billing systems—such as retail, utilities, and financial services—are particularly at risk. The lack of authentication requirement increases the threat surface, as attackers can exploit the vulnerability remotely without credentials. However, the absence of known exploits in the wild currently reduces immediate risk, but proactive remediation is critical to prevent future attacks.

To mitigate CVE-2025-65380, organizations should immediately review the PHPGurukul Billing System source code, focusing on the admin/index.php endpoint. The primary fix is to refactor the SQL query construction to use parameterized queries or prepared statements, which safely handle user input and prevent injection. Input validation should be implemented to enforce strict constraints on the username parameter, such as allowed character sets and length limits. If possible, restrict access to the administrative interface via network segmentation, VPNs, or IP whitelisting to reduce exposure. Regularly monitor logs for suspicious query patterns or repeated failed login attempts that could indicate exploitation attempts. Since no official patches are available, consider applying custom code fixes or contacting the vendor for updates. Additionally, conduct security testing, including automated scanning and manual penetration testing, to verify the vulnerability is remediated. Finally, ensure backups of billing data are maintained securely to enable recovery in case of data integrity compromise.