CVE-2025-11115 is a SQL Injection vulnerability identified in version 1.0 of the code-projects Simple Scheduling System, specifically within the /addtime.php file. The vulnerability arises due to improper sanitization or validation of the 'starttime' and 'endtime' parameters, which are used in SQL queries. An attacker can manipulate these parameters to inject malicious SQL code, potentially altering the intended database queries. This flaw allows remote exploitation without requiring authentication or user interaction, as indicated by the CVSS vector (AV:N/AC:L/AT:N/PR:N/UI:N). The vulnerability impacts the confidentiality, integrity, and availability of the underlying database, as attackers could extract sensitive scheduling data, modify records, or disrupt service availability. The CVSS score of 6.9 (medium severity) reflects the moderate impact and ease of exploitation. Although no public exploits are currently known in the wild, the vulnerability has been publicly disclosed, increasing the risk of exploitation by opportunistic attackers. The absence of patches or vendor-provided fixes at the time of disclosure further elevates the threat. Given the nature of scheduling systems, which often contain sensitive organizational and personnel data, exploitation could lead to unauthorized data access, manipulation of schedules, or denial of service conditions affecting business operations.

For European organizations using the Simple Scheduling System 1.0, this vulnerability poses a tangible risk to operational continuity and data security. Scheduling systems often manage critical resources such as employee shifts, meeting rooms, and project timelines. Exploitation could lead to unauthorized disclosure of sensitive scheduling information, impacting privacy compliance obligations under GDPR. Integrity violations could disrupt organizational workflows, causing operational delays or conflicts. Availability impacts could result in denial of service, affecting business productivity. Additionally, compromised scheduling data could be leveraged in targeted attacks or social engineering campaigns. The risk is heightened for sectors with stringent data protection requirements, such as healthcare, finance, and government agencies within Europe. The remote and unauthenticated nature of the exploit means attackers can attempt exploitation from outside the network perimeter, increasing exposure. The lack of patches necessitates immediate attention to prevent potential exploitation, especially as public disclosure may attract attackers.

Given the absence of official patches, European organizations should implement immediate compensating controls. First, restrict external access to the affected /addtime.php endpoint via network segmentation, firewalls, or web application firewalls (WAFs) with custom rules to detect and block SQL injection patterns targeting 'starttime' and 'endtime' parameters. Conduct thorough input validation and sanitization at the application layer if source code access is available, employing parameterized queries or prepared statements to eliminate injection vectors. Monitor web server and database logs for anomalous query patterns or repeated access attempts to the vulnerable endpoint. Employ intrusion detection/prevention systems (IDS/IPS) tuned to detect SQL injection signatures. If feasible, isolate or temporarily disable the vulnerable scheduling system until a vendor patch or update is available. Additionally, review and enforce the principle of least privilege on database accounts used by the application to limit the potential damage of a successful injection. Finally, maintain up-to-date backups of scheduling data to enable recovery in case of data corruption or loss.