CVE-2023-53154 is a vulnerability identified in the cJSON project, specifically affecting versions prior to 1.7.18. The issue is classified as a CWE-125: Out-of-bounds Read, which occurs in the parse_string function when processing JSON input. The vulnerability arises when cJSON_ParseWithLength is called with a JSON string such as {"1":1, that lacks a trailing newline. Under these conditions, a heap-based buffer over-read can occur, meaning the parser reads beyond the allocated memory buffer. This can lead to undefined behavior including potential application crashes or information leakage. The vulnerability has a CVSS v3.1 base score of 2.9, indicating a low severity level. The vector details specify that the attack requires local access (AV:L), high attack complexity (AC:H), no privileges (PR:N), no user interaction (UI:N), and impacts only availability (A:L) without affecting confidentiality or integrity. No known exploits are currently reported in the wild, and no patches are linked yet. The vulnerability primarily affects software that uses cJSON for JSON parsing and that calls cJSON_ParseWithLength with specially crafted input lacking a trailing newline, which may be uncommon in typical usage scenarios.

For European organizations, the impact of CVE-2023-53154 is generally limited due to its low severity and the requirement for local access and high attack complexity. However, organizations that embed cJSON in their software products or internal tools—especially those processing JSON data from local sources—could experience application instability or crashes if exposed to malformed JSON inputs exploiting this vulnerability. This could lead to denial of service conditions affecting availability of critical services. Since the vulnerability does not compromise confidentiality or integrity, the risk of data breaches or unauthorized data modification is minimal. Nevertheless, in environments where high availability is critical, such as financial services or healthcare sectors prevalent in Europe, even low-severity availability issues can have operational impacts. Additionally, software vendors and developers in Europe using cJSON should be aware of this vulnerability to prevent indirect exposure through their products.

To mitigate CVE-2023-53154, European organizations and developers should: 1) Upgrade to cJSON version 1.7.18 or later once it is released, as it is expected to contain the fix for this vulnerability. 2) In the interim, implement input validation and sanitization to ensure JSON strings passed to cJSON_ParseWithLength always include proper termination such as trailing newlines, preventing the triggering of the out-of-bounds read. 3) Restrict local access to systems running vulnerable software to trusted users only, minimizing the risk of exploitation. 4) Employ runtime protections such as memory safety tools (e.g., AddressSanitizer) during development and testing to detect and prevent buffer over-read conditions. 5) Monitor application logs for crashes or anomalies related to JSON parsing that could indicate attempted exploitation. 6) For software vendors, conduct thorough code reviews and fuzz testing on JSON parsing components to identify and remediate similar issues proactively.