CVE-2022-23459 is a use-after-free and double-free vulnerability identified in the Jsonxx (also known as Json++) library, a C++ JSON parser, writer, and reader. The vulnerability arises from the improper handling of the Value class within Jsonxx. Specifically, the default assignment operator of the Value class can be used with pointer types that point to mutable data without updating the pointer itself. This leads to scenarios where memory may be freed multiple times (double free) or accessed after it has been freed (use after free), resulting in memory corruption. Such memory corruption can cause undefined behavior, including application crashes, data corruption, or potentially arbitrary code execution if exploited. The Jsonxx project has been archived and is no longer maintained, meaning no patches or updates are forthcoming to address this vulnerability. The affected versions are unspecified but presumed to include all versions of Jsonxx prior to archiving. No known exploits have been reported in the wild to date. Given the nature of the vulnerability, exploitation would typically require the attacker to influence or control JSON data processed by the vulnerable application, potentially requiring some level of user interaction or input injection. The vulnerability affects the confidentiality, integrity, and availability of applications using Jsonxx due to the risk of memory corruption and potential arbitrary code execution.

For European organizations, the impact of this vulnerability depends largely on the extent to which Jsonxx is used within their software stacks. Organizations relying on legacy or embedded systems that incorporate Jsonxx for JSON processing may be at risk. Exploitation could lead to application crashes, denial of service, or in worst cases, remote code execution, compromising system integrity and availability. This is particularly critical for sectors with high reliance on embedded or legacy C++ applications, such as industrial control systems, telecommunications, and certain financial services. The lack of ongoing maintenance for Jsonxx increases the risk profile, as no official patches or mitigations will be released, forcing organizations to seek alternative JSON libraries or implement custom mitigations. The vulnerability could also be leveraged as an initial attack vector in multi-stage attacks targeting sensitive data or critical infrastructure. Given the absence of known exploits, the immediate risk is moderate, but the potential impact on confidentiality, integrity, and availability remains significant if exploited.

1. Immediate replacement of Jsonxx with a modern, actively maintained JSON library that provides robust memory management and security guarantees, such as RapidJSON, nlohmann/json, or similar. 2. Conduct a thorough audit of all internal and third-party software to identify any usage of Jsonxx, including embedded systems and legacy applications. 3. Where replacement is not immediately feasible, implement strict input validation and sanitization on all JSON data processed by applications using Jsonxx to reduce the risk of maliciously crafted inputs triggering the vulnerability. 4. Employ runtime memory protection mechanisms such as AddressSanitizer (ASan) during development and testing to detect use-after-free and double-free errors early. 5. Increase monitoring and logging around applications using Jsonxx to detect abnormal crashes or behavior that may indicate exploitation attempts. 6. For critical systems, consider network segmentation and application-layer firewalls to limit exposure to untrusted inputs that could exploit this vulnerability. 7. Engage with software vendors and suppliers to confirm whether their products use Jsonxx and advocate for timely remediation or product updates.