CVE-2025-57052 is a critical security vulnerability affecting the cJSON library versions 1.5.0 through 1.7.18. The vulnerability arises from an out-of-bounds access issue in the decode_array_index_from_pointer function within the cJSON_Utils.c source file. Specifically, this function improperly handles malformed JSON pointer strings containing alphanumeric characters, allowing attackers to bypass array bounds checking. This leads to unauthorized access to memory regions outside the intended array boundaries. Because cJSON is a widely used lightweight C library for parsing and manipulating JSON data, this flaw can be exploited remotely without any authentication or user interaction, as indicated by the CVSS vector (AV:N/AC:L/PR:N/UI:N). The vulnerability impacts confidentiality, integrity, and availability, as attackers can read or potentially manipulate restricted data, cause memory corruption, or trigger application crashes. The underlying weaknesses correspond to CWE-129 (Improper Validation of Array Index) and CWE-125 (Out-of-bounds Read), both of which are serious memory safety issues. Although no known exploits are reported in the wild yet, the high CVSS score of 9.8 reflects the ease of exploitation and severe impact. The lack of available patches at the time of publication increases the urgency for affected organizations to implement mitigations and monitor for updates. Given the widespread adoption of cJSON in embedded systems, IoT devices, and various software products, this vulnerability poses a significant risk across multiple sectors.

For European organizations, the impact of CVE-2025-57052 can be substantial. Many European industries rely on embedded systems and IoT devices that incorporate cJSON for JSON parsing, including automotive, manufacturing, telecommunications, and critical infrastructure sectors. Exploitation could lead to unauthorized data disclosure, manipulation of operational parameters, or denial of service through application crashes. This is particularly concerning for sectors under strict data protection regulations such as GDPR, where confidentiality breaches can result in heavy fines and reputational damage. Furthermore, the vulnerability's remote exploitability without authentication means attackers can target exposed network services or devices directly, increasing the attack surface. Industrial control systems and smart city infrastructure in Europe that use cJSON-based components could be disrupted, impacting public safety and economic activities. The vulnerability also raises concerns for software vendors and service providers who integrate cJSON in their products, as downstream customers may be affected. Overall, the threat could undermine trust in digital services and require significant incident response efforts.

Given the absence of official patches at the time of disclosure, European organizations should take immediate and specific mitigation steps beyond generic advice: 1) Conduct an inventory to identify all software and devices using cJSON versions 1.5.0 through 1.7.18. 2) Where possible, isolate or restrict network access to systems running vulnerable cJSON versions to limit exposure to remote attacks. 3) Employ application-layer firewalls or intrusion prevention systems with custom rules to detect and block malformed JSON pointer strings that could exploit this vulnerability. 4) Engage with software vendors and device manufacturers to obtain timelines for patches or updates addressing this issue. 5) Implement runtime protections such as memory safety tools (e.g., AddressSanitizer) in development and testing environments to detect out-of-bounds accesses. 6) Monitor logs and network traffic for anomalous JSON pointer usage indicative of exploitation attempts. 7) Plan for rapid deployment of patches once available, including regression testing to ensure stability. 8) For critical systems, consider temporary mitigation by disabling or limiting JSON pointer functionality if feasible. These targeted actions will reduce the risk of exploitation while awaiting official fixes.