CVE-2025-6731 is a path traversal vulnerability identified in the yzcheng90 X-SpringBoot framework, specifically affecting version 5.0. The vulnerability resides in the uploadApk function within the /sys/oss/upload/apk endpoint, which handles APK file uploads. The flaw arises from insufficient validation or sanitization of the 'File' argument, allowing an attacker to manipulate the file path and traverse directories outside the intended upload directory. This can lead to unauthorized access or modification of files on the server's filesystem. The vulnerability is remotely exploitable without requiring user interaction or prior authentication, increasing its risk profile. Although the CVSS 4.0 score is 5.3 (medium severity), the ability to perform path traversal remotely and potentially access sensitive files or overwrite critical files can have serious consequences. The vendor has not responded to disclosure attempts, and no patches are currently available. Public exploit code has been disclosed, which raises the likelihood of exploitation in the wild. The vulnerability impacts the confidentiality and integrity of the affected systems, with limited impact on availability. The attack complexity is low, and no privileges or user interaction are required, making exploitation feasible for attackers with network access to the vulnerable endpoint. The scope is limited to systems running X-SpringBoot version 5.0 with the vulnerable APK upload component enabled.

For European organizations using the X-SpringBoot framework version 5.0, this vulnerability poses a significant risk to the confidentiality and integrity of their systems. Attackers could exploit the path traversal to read sensitive configuration files, credentials, or proprietary data stored on the server, or potentially overwrite critical files to disrupt operations or implant backdoors. This could lead to data breaches, intellectual property theft, or system compromise. Given that the vulnerability is remotely exploitable without authentication, exposed web services using this component are at heightened risk. Organizations in sectors with strict data protection regulations such as GDPR (e.g., finance, healthcare, government) may face compliance violations and reputational damage if exploited. The lack of vendor response and absence of patches means organizations must rely on mitigations or consider alternative frameworks. The medium CVSS score may underestimate the real-world impact due to the ease of exploitation and potential for sensitive data exposure. Overall, the threat could disrupt business continuity and expose sensitive data, especially in environments where X-SpringBoot is used for critical applications or public-facing services.

Since no official patch is currently available, European organizations should implement immediate compensating controls. First, restrict network access to the vulnerable upload endpoint by applying firewall rules or web application firewall (WAF) policies to limit access to trusted IPs only. Second, implement strict input validation and sanitization at the application or proxy level to block path traversal patterns such as '../' sequences in file upload parameters. Third, monitor logs for suspicious activity targeting the /sys/oss/upload/apk endpoint, including unusual file path requests or repeated attempts to access parent directories. Fourth, consider disabling or temporarily removing the APK upload functionality if not essential. Fifth, conduct a thorough audit of file permissions on the server to ensure the application runs with the least privilege necessary, limiting the impact of any successful traversal. Finally, organizations should track vendor communications for patches or updates and plan for timely application once available. Employing runtime application self-protection (RASP) tools or endpoint detection and response (EDR) solutions may also help detect exploitation attempts in real time.