CVE-2022-49186 is a vulnerability identified in the Linux kernel, specifically within the clock subsystem's visconti driver. The issue arises from improper handling of an array index in the function visconti_clk_register_gates(). The code uses the value -1 to indicate the absence of a reset function, but this value is stored in an unsigned 8-bit integer (u8). Because u8 cannot represent negative numbers, the -1 value is interpreted as 255, causing the conditional check if (clks[i].rs_id >= 0) to always evaluate as true. This logic flaw leads to an out-of-bounds array access when the function attempts to register clock gates. Out-of-bounds access vulnerabilities can lead to undefined behavior, including memory corruption, kernel crashes, or potential escalation of privileges if exploited. Although no known exploits are currently reported in the wild, the vulnerability affects the Linux kernel's clock management code, which is critical for hardware timing and power management. The affected versions include specific commits identified by their hashes, indicating that the vulnerability is present in certain kernel builds prior to the patch. The patch or fix details are not provided in the source information, but the issue has been publicly disclosed and assigned a CVE identifier. This vulnerability is technical and low-level, requiring kernel-level access or the ability to load kernel modules or interact with the clock subsystem to exploit. The lack of a CVSS score suggests that the vulnerability's impact and exploitability have not yet been fully assessed or published.

For European organizations, the impact of CVE-2022-49186 depends on their use of Linux-based systems, particularly those running kernels with the affected visconti clock driver. Organizations relying on embedded Linux devices, industrial control systems, or specialized hardware that use this clock driver could face risks of system instability or potential privilege escalation if an attacker exploits this vulnerability. The out-of-bounds access could lead to kernel crashes, causing denial of service, or potentially allow attackers to execute arbitrary code with kernel privileges, compromising system confidentiality, integrity, and availability. Given that Linux is widely used across European enterprises, cloud providers, and critical infrastructure, the vulnerability could affect servers, IoT devices, and network equipment. However, exploitation complexity is relatively high, requiring local access or specific conditions to trigger the vulnerability. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially for organizations with high-value targets or those in sectors like finance, healthcare, or government where Linux kernel security is paramount.

European organizations should prioritize updating their Linux kernels to versions that include the patch for CVE-2022-49186 once available from their distribution vendors or kernel maintainers. Since the vulnerability involves kernel-level code, applying official kernel updates or patches is the most effective mitigation. Organizations should audit their systems to identify devices running affected kernel versions, especially embedded or specialized hardware using the visconti clock driver. Restricting local access and limiting the ability to load or modify kernel modules can reduce exploitation risk. Employing kernel security modules (e.g., SELinux, AppArmor) to enforce strict access controls and monitoring kernel logs for unusual behavior related to clock subsystem operations can help detect exploitation attempts. Additionally, organizations should follow secure development and deployment practices for Linux-based systems and maintain up-to-date inventories of hardware and software to rapidly respond to such vulnerabilities. For critical infrastructure, consider network segmentation and isolation of vulnerable devices until patches are applied.