CVE-2025-47868 is a security vulnerability identified in the Apache NuttX Real-Time Operating System (RTOS), specifically within the tools/bdf-converter utility. This utility is a standalone font conversion tool used to process BDF (Bitmap Distribution Format) font files. The vulnerability is classified as an out-of-bounds write (CWE-787), which can lead to a heap-based buffer overflow (CWE-122). This occurs when the bdf-converter processes external user-supplied data without adequate bounds checking, allowing it to write data beyond the allocated memory buffer. Although the bdf-converter is not part of the core NuttX RTOS or its runtime applications, users who actively employ this tool—especially in automated or publicly exposed environments—may be at risk. The affected versions of Apache NuttX range from 6.9 up to but not including 12.9.0, with the vulnerability fixed in version 12.9.0. No known exploits are currently reported in the wild, and no CVSS score has been assigned to this vulnerability yet. The risk arises primarily when untrusted input is processed by the bdf-converter, potentially allowing an attacker to corrupt memory, which could lead to arbitrary code execution, denial of service, or system instability depending on the context of use.

For European organizations, the impact of this vulnerability depends largely on the deployment and usage of Apache NuttX RTOS and specifically the bdf-converter tool. NuttX is commonly used in embedded systems, IoT devices, and real-time applications such as industrial control, automotive systems, and aerospace. If organizations use the bdf-converter in automated pipelines or expose it to untrusted input (e.g., through public APIs or shared environments), attackers could exploit this vulnerability to execute arbitrary code or cause denial of service. This could compromise the confidentiality, integrity, and availability of critical embedded systems, potentially disrupting industrial operations or safety-critical functions. Since the bdf-converter is optional and not part of the runtime, the attack surface is limited to environments where this tool is actively used. However, given the increasing reliance on embedded systems in sectors like manufacturing, transportation, and energy within Europe, the vulnerability could have significant operational and safety implications if exploited.

European organizations using Apache NuttX RTOS should immediately upgrade to version 12.9.0 or later, where this vulnerability is patched. For environments where upgrading is not immediately feasible, organizations should restrict access to the bdf-converter tool, ensuring it is not exposed to untrusted or external input sources. Implement strict input validation and sanitization on any data processed by the bdf-converter to prevent malformed or malicious font files from triggering the vulnerability. Additionally, isolate the execution environment of the bdf-converter using containerization or sandboxing techniques to limit the impact of potential exploitation. Monitoring and logging usage of the bdf-converter can help detect anomalous activity. Finally, review and audit automated workflows that incorporate the bdf-converter to ensure they do not process untrusted data without proper controls.