CVE-2025-55297 is a medium-severity buffer overflow vulnerability identified in the Espressif Internet of Things Development Framework (ESP-IDF), specifically within the BluFi example implementation. The vulnerability arises from improper handling of buffer sizes during two critical operations: Wi-Fi credential processing and the Diffie–Hellman key exchange mechanism. These operations are fundamental for establishing secure wireless connections and cryptographic key agreements in IoT devices using ESP-IDF. The flaw is classified under CWE-120 (Classic Buffer Overflow) and CWE-131 (Incorrect Calculation of Buffer Size), indicating that the code copies data into buffers without adequate size verification, potentially leading to memory corruption. Exploitation of this vulnerability could allow an attacker to overwrite memory regions, which may lead to arbitrary code execution, denial of service, or leakage of sensitive information. The vulnerability affects multiple versions of ESP-IDF prior to fixed releases 5.4.1, 5.3.3, 5.1.6, and 5.0.9. The CVSS 4.0 base score is 5.2, reflecting a medium severity with attack vector being adjacent network (AV:A), low attack complexity, no privileges required, and no user interaction needed. The impact on confidentiality, integrity, and availability is high if exploited. No known exploits are currently reported in the wild. This vulnerability is particularly relevant for IoT devices leveraging ESP-IDF for Wi-Fi connectivity and secure communications, which are widely used in embedded systems, smart home devices, and industrial IoT applications.

For European organizations, the impact of CVE-2025-55297 can be significant, especially for sectors relying heavily on IoT deployments such as manufacturing, smart cities, healthcare, and critical infrastructure. Exploitation could lead to unauthorized access to network credentials, enabling lateral movement within corporate or operational networks. The compromise of Diffie–Hellman key exchange processes could undermine cryptographic protections, exposing sensitive data or allowing man-in-the-middle attacks. This could result in operational disruptions, data breaches, and loss of trust. Given the proliferation of ESP-IDF-based devices in Europe, including consumer and industrial IoT products, organizations face risks of device compromise, service outages, and potential regulatory penalties under GDPR if personal data confidentiality is breached. The medium CVSS score suggests that while exploitation is feasible, it requires network adjacency, limiting remote exploitation but still posing a threat within local or segmented networks.

European organizations should prioritize updating ESP-IDF to the patched versions 5.4.1, 5.3.3, 5.1.6, or 5.0.9 depending on their current deployment. Beyond patching, organizations should conduct thorough inventories of IoT devices using ESP-IDF to identify vulnerable versions. Network segmentation should be enforced to isolate IoT devices from critical infrastructure and sensitive data environments, reducing the attack surface. Implement strict access controls and monitoring on wireless networks to detect anomalous activities indicative of exploitation attempts. Employ runtime protections such as stack canaries and address space layout randomization (ASLR) where supported by the device hardware and firmware. Additionally, review and harden Wi-Fi credential management processes and cryptographic implementations in custom applications built on ESP-IDF. Engage with device manufacturers to ensure timely firmware updates and security patches. Finally, incorporate vulnerability scanning and penetration testing focused on IoT devices to proactively identify and remediate weaknesses.