CVE-2022-42227 is a high-severity vulnerability identified as a heap-buffer-overflow in the jsonlint 1.0 tool, specifically within the lexer component located at /home/hjsz/jsonlint/src/lexer. A heap-buffer-overflow occurs when a program writes more data to a heap-allocated buffer than it was allocated to hold, potentially leading to memory corruption, crashes, or arbitrary code execution. Jsonlint is a JSON validation tool used to parse and validate JSON data structures. Although the vendor and product details are unspecified, the vulnerability affects jsonlint version 1.0. The CVSS 3.1 base score is 7.5, indicating a high severity, with the vector AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. This means the vulnerability is remotely exploitable over the network without any privileges or user interaction, and it impacts availability only, not confidentiality or integrity. The CWE classification is CWE-787, which corresponds to out-of-bounds writes. No patches or known exploits in the wild have been reported as of the publication date (October 19, 2022). The vulnerability could be triggered by specially crafted JSON input that causes the lexer to write beyond the allocated heap buffer, leading to application crashes or denial of service. Given the nature of jsonlint as a developer or CI tool, exploitation could disrupt automated JSON validation processes or services relying on jsonlint for JSON parsing and validation.

For European organizations, the primary impact of this vulnerability is a potential denial of service (DoS) condition affecting systems that utilize jsonlint 1.0 for JSON validation. This could disrupt development pipelines, automated testing, or any service that integrates jsonlint for JSON parsing, potentially causing downtime or delays in software delivery. Since the vulnerability does not affect confidentiality or integrity, data breaches or unauthorized data modification are unlikely. However, availability impacts can still have significant operational consequences, especially in environments where JSON validation is critical for service orchestration or API gateways. Organizations relying on jsonlint in production or critical infrastructure should be aware of this risk. The lack of required privileges and user interaction means attackers could remotely trigger the overflow if jsonlint is exposed as a service or integrated into network-facing applications, increasing the attack surface. Although no known exploits are reported, the ease of exploitation and high CVSS score suggest that threat actors could develop exploits, making proactive mitigation important.

Since no official patches are currently available, European organizations should consider the following specific mitigations: 1) Identify and inventory all instances of jsonlint 1.0 usage within development, testing, and production environments. 2) Where possible, isolate jsonlint usage to internal, non-network-exposed environments to reduce remote attack vectors. 3) Implement input validation and sanitization on JSON data before it reaches jsonlint to reduce the risk of malformed inputs triggering the overflow. 4) Monitor application logs and system behavior for crashes or abnormal terminations related to jsonlint processes, enabling early detection of exploitation attempts. 5) Consider replacing jsonlint 1.0 with alternative JSON validation tools that are actively maintained and free from this vulnerability. 6) Employ runtime protections such as memory safety tools (e.g., AddressSanitizer) during development to detect and prevent heap overflows. 7) Stay informed on vendor updates or community patches and apply them promptly once available. 8) If jsonlint is integrated into CI/CD pipelines, implement fail-safes to prevent pipeline-wide failures due to jsonlint crashes.