CVE-2024-1111 is a cross-site scripting (XSS) vulnerability identified in version 1.0 of the SourceCodester QR Code Login System, specifically within the add-user.php file. The vulnerability arises from improper sanitization or validation of the 'qr-code' parameter, which can be manipulated by an attacker to inject malicious scripts. This vulnerability is classified under CWE-79, indicating that it is a reflected or stored XSS issue. The attack vector is remote and does not require authentication, but it does require user interaction, such as a victim clicking a crafted link or visiting a malicious webpage that triggers the vulnerable parameter. The CVSS 3.1 base score is 4.3, indicating a medium severity level. The impact primarily affects the integrity of the system, as the attacker can execute scripts in the context of the victim's browser, potentially leading to session hijacking, defacement, or redirection to malicious sites. Confidentiality and availability impacts are not directly affected by this vulnerability. No known exploits are currently reported in the wild, and no patches have been published yet. The vulnerability affects only version 1.0 of the product, which is a specialized QR code login system likely used in web applications for authentication purposes.

For European organizations using SourceCodester QR Code Login System 1.0, this vulnerability poses a risk of client-side script injection that can compromise user sessions and trust. While the direct impact on backend systems is limited, the exploitation of this XSS flaw can lead to phishing attacks, credential theft, or unauthorized actions performed on behalf of legitimate users. This can result in reputational damage, loss of customer trust, and potential regulatory scrutiny under GDPR if personal data is compromised through session hijacking or data exfiltration. Organizations relying on this system for authentication should be aware that attackers can remotely exploit this vulnerability without needing credentials, increasing the risk profile. However, since the vulnerability requires user interaction, the risk can be somewhat mitigated by user awareness and security controls. The lack of known exploits in the wild suggests limited immediate threat but does not preclude future exploitation attempts.

To mitigate this vulnerability, European organizations should first assess whether they are using SourceCodester QR Code Login System version 1.0. If so, immediate steps should include implementing strict input validation and output encoding on the 'qr-code' parameter within add-user.php to neutralize malicious scripts. Employing Content Security Policy (CSP) headers can further reduce the risk by restricting the execution of unauthorized scripts. Organizations should also conduct security awareness training to educate users about the risks of clicking unknown links or interacting with suspicious QR codes. Monitoring web application logs for unusual input patterns targeting the 'qr-code' parameter can help detect exploitation attempts. Since no official patch is currently available, organizations might consider isolating or replacing the vulnerable component with a more secure alternative. Additionally, employing web application firewalls (WAFs) with rules to detect and block XSS payloads targeting this parameter can provide a compensating control until a patch is released.