CVE-2025-11115 is a SQL injection vulnerability affecting the Simple Scheduling System version 1.0 developed by code-projects. The vulnerability exists in the /addtime.php endpoint, where the parameters starttime and endtime are not properly sanitized before being used in SQL queries. This flaw allows an unauthenticated remote attacker to inject arbitrary SQL commands, potentially enabling unauthorized data access, modification, or deletion within the backend database. The vulnerability does not require user interaction or privileges, making it easily exploitable over the network. The CVSS 4.0 base score is 6.9 (medium severity), reflecting the network attack vector, low complexity, and no required authentication. The impact includes partial compromise of confidentiality, integrity, and availability of data managed by the scheduling system. Although no exploits have been observed in the wild yet, the public disclosure of the vulnerability and its exploitability make it a credible threat. The lack of official patches or mitigations from the vendor increases the urgency for organizations to implement their own protective measures. This vulnerability is particularly concerning for organizations relying on this scheduling system for critical operations, as attackers could manipulate scheduling data or extract sensitive information.

For European organizations using the Simple Scheduling System 1.0, this vulnerability poses a risk of unauthorized access to scheduling data, which may include sensitive personal or operational information. Exploitation could lead to data breaches, manipulation of scheduling records, or denial of service by corrupting database entries. This can disrupt business operations, especially in sectors relying heavily on scheduling such as healthcare, transportation, and manufacturing. The partial compromise of confidentiality and integrity could also lead to regulatory non-compliance under GDPR if personal data is exposed or altered. Additionally, the availability impact, while limited, could affect service continuity. The remote and unauthenticated nature of the exploit increases the attack surface, making it easier for threat actors to target vulnerable systems across Europe. Organizations may face reputational damage and financial losses if exploited.

Since no official patches are currently available, European organizations should immediately implement input validation and sanitization on the starttime and endtime parameters within /addtime.php or at the web application firewall (WAF) level. Employ parameterized queries or prepared statements to prevent SQL injection. Conduct a thorough code review of the scheduling system to identify and remediate other potential injection points. Deploy network-level protections such as WAF rules specifically targeting SQL injection patterns related to these parameters. Monitor logs for unusual database queries or errors that could indicate exploitation attempts. Restrict access to the scheduling system to trusted networks or VPNs where possible. Plan for an upgrade or replacement of the vulnerable software version once a vendor patch is released. Additionally, conduct regular backups of scheduling data to enable recovery in case of data corruption or loss.