CVE-2025-68474 is an out-of-bounds write vulnerability classified under CWE-787 found in the Espressif Internet of Things Development Framework (ESP-IDF), specifically within the BlueDroid AVRCP stack's avrc_vendor_msg() function. The vulnerability exists because the buffer size allocated for handling AVRCP vendor commands is validated against a constant AVRC_MIN_CMD_LEN (20 bytes), which is insufficient. The actual fixed header data written before the vendor payload is 29 bytes, exceeding the allocated buffer size. When the vendor_len parameter approaches the buffer limit, this discrepancy allows writes beyond the allocated memory boundary. This memory corruption can lead to crashes or undefined behavior, and the overflow risk increases when assertions are disabled in the build. The affected versions include ESP-IDF releases from 5.1.6 up to 5.5.1 and their beta variants. The vulnerability requires an attacker to send crafted AVRCP vendor commands over Bluetooth, which implies network-level access but no authentication or user interaction is necessary. The CVSS 4.0 score is 6.1 (medium), reflecting the moderate impact and attack complexity. No public exploits have been reported yet, but the flaw could be leveraged for denial of service or potentially arbitrary code execution in certain contexts. The lack of patches at the time of reporting necessitates cautious handling and monitoring for updates from Espressif.

For European organizations, the impact of CVE-2025-68474 depends largely on their use of Espressif ESP-IDF-based devices, particularly those employing Bluetooth AVRCP profiles. Industries with widespread IoT deployments—such as manufacturing automation, smart building controls, automotive infotainment, and consumer electronics—may face risks of device instability or crashes due to memory corruption. This could disrupt operational continuity, degrade user experience, or open avenues for further exploitation if attackers achieve code execution. Given the medium severity and the need for network-level Bluetooth access, the threat is more pronounced in environments with exposed or poorly secured Bluetooth interfaces. Critical infrastructure relying on Bluetooth-enabled IoT devices could experience availability issues or require costly incident response. Additionally, the vulnerability could undermine trust in IoT deployments, impacting compliance with European cybersecurity regulations like NIS2. The absence of known exploits reduces immediate risk but does not eliminate the potential for future attacks, especially as adversaries often target IoT ecosystems.

European organizations should prioritize upgrading ESP-IDF to versions beyond 5.5.1 once Espressif releases patches addressing CVE-2025-68474. Until patches are available, implement strict network segmentation to isolate Bluetooth-enabled devices from untrusted networks and restrict Bluetooth access to authorized personnel and devices only. Employ Bluetooth security best practices such as disabling unused profiles, enforcing strong pairing mechanisms, and monitoring Bluetooth traffic for anomalous AVRCP commands. Conduct thorough firmware audits to identify devices running vulnerable ESP-IDF versions and plan for timely updates. Where feasible, apply runtime protections like stack canaries and address sanitizers during development to detect memory corruption. Additionally, collaborate with device manufacturers to ensure secure firmware supply chains and request vulnerability disclosures and patches. Maintain up-to-date asset inventories to track affected devices and incorporate this vulnerability into risk assessments and incident response plans. Finally, raise awareness among operational technology teams about the risks of Bluetooth vulnerabilities in IoT environments.