CVE-2022-49189 is a vulnerability identified in the Linux kernel specifically related to the Qualcomm clock framework component clk-rcg2. The issue arises from the logic used to calculate the 'D' value in the clock rate generator (RCG) for display pixel clocks on certain newer platforms. The display pixel clock requires support for fractional M/N ratios, such as 2/3, to properly configure the clock frequency. However, the existing implementation did not validate whether the computed 'D' value fell within an acceptable range for the given M and N values. This lack of validation can lead to underflow errors during the calculation of the final 'D' value. Underflow errors in clock configuration can cause incorrect clock rates, potentially resulting in display malfunctions or instability in the affected hardware platforms. The vulnerability was addressed by updating the logic to ensure the final 'D' value is correctly calculated and constrained within the valid range, preventing underflow conditions. The affected versions are identified by specific Linux kernel commit hashes, indicating this is a low-level kernel issue affecting certain Qualcomm-based platforms. There are no known exploits in the wild at the time of publication, and no CVSS score has been assigned yet. The vulnerability is technical and specific to hardware clock configuration, which may affect devices relying on the Qualcomm clk-rcg2 driver within the Linux kernel.

For European organizations, the impact of CVE-2022-49189 depends largely on the deployment of Linux systems running on Qualcomm-based hardware platforms that utilize the clk-rcg2 clock framework, particularly those handling display pixel clocks. Potential impacts include system instability, display errors, or hardware malfunctions due to incorrect clock rates. This could affect embedded systems, mobile devices, or specialized industrial equipment running Linux with Qualcomm chipsets. In environments where display functionality is critical, such as digital signage, kiosks, or control systems, this vulnerability could lead to operational disruptions. However, since the vulnerability relates to clock configuration and does not directly expose a remote code execution or privilege escalation vector, the confidentiality and integrity impacts are limited. Availability may be affected if the hardware or system becomes unstable or fails to operate correctly. The absence of known exploits reduces immediate risk, but unpatched systems remain vulnerable to potential future exploitation or operational issues. Organizations relying on Linux kernel versions with this flaw should prioritize patching to maintain system stability and reliability.

To mitigate CVE-2022-49189, European organizations should: 1) Identify all Linux systems running on Qualcomm-based hardware platforms, especially those using the clk-rcg2 driver for display pixel clocks. 2) Apply the latest Linux kernel updates or patches that include the fix for this vulnerability, ensuring the updated logic for calculating the 'D' value is in place. 3) For embedded or specialized devices where kernel updates are less frequent, coordinate with hardware vendors or device manufacturers to obtain firmware or kernel patches. 4) Conduct thorough testing of display and clock functionality post-patch to confirm stability and correct operation. 5) Monitor vendor advisories and Linux kernel mailing lists for any emerging exploit information or additional patches. 6) Implement hardware and software inventory management to track affected devices and ensure timely patch deployment. 7) Where immediate patching is not feasible, consider isolating affected devices from critical networks to reduce potential impact from instability or future exploitation attempts.