CVE-2025-11476 identifies a SQL injection vulnerability in SourceCodester Simple E-Commerce Bookstore version 1.0, specifically within the /index.php file's login_username parameter. This parameter is vulnerable due to insufficient input sanitization, enabling attackers to craft malicious SQL payloads that the backend database executes. The vulnerability is remotely exploitable without requiring authentication or user interaction, making it highly accessible to attackers. The CVSS 4.0 base score is 6.9, reflecting a medium severity level, with attack vector network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), and no user interaction (UI:N). The impact includes partial loss of confidentiality, integrity, and availability, as attackers can retrieve, modify, or delete sensitive data stored in the database. Although no active exploitation has been reported, the availability of public exploits increases the likelihood of future attacks. The vulnerability affects only version 1.0 of the product, which is a simple e-commerce bookstore solution commonly used by small to medium-sized businesses. The lack of vendor patches or official remediation guidance necessitates immediate defensive measures by users.

For European organizations, exploitation of this SQL injection vulnerability could lead to unauthorized access to customer data, including personal and payment information, resulting in data breaches and regulatory non-compliance under GDPR. Integrity of transaction records could be compromised, leading to financial discrepancies and loss of trust. Availability of the e-commerce platform might be disrupted through database manipulation or denial-of-service conditions. Small and medium enterprises using this software are particularly at risk due to limited security resources. The reputational damage and potential fines from data protection authorities could be significant. Furthermore, attackers could leverage the compromised systems as footholds for broader network intrusion. Given the remote and unauthenticated nature of the exploit, the threat is substantial for any European entity relying on this vulnerable software.

Since no official patches are currently available, European organizations should immediately implement the following mitigations: 1) Apply strict input validation and sanitization on the login_username parameter to block SQL metacharacters and unexpected input patterns. 2) Refactor the application code to use parameterized queries or prepared statements to prevent SQL injection. 3) Employ web application firewalls (WAFs) with custom rules targeting SQL injection signatures specific to this vulnerability. 4) Monitor database logs and application logs for unusual query patterns or failed login attempts indicative of exploitation attempts. 5) Restrict database user privileges to the minimum necessary to limit potential damage. 6) Consider isolating or temporarily disabling the vulnerable login functionality until a patch or secure update is available. 7) Educate development and security teams about secure coding practices to prevent similar vulnerabilities. 8) Regularly back up critical data to enable recovery in case of compromise.