CVE-2021-47447 is a vulnerability identified in the Linux kernel, specifically within the Direct Rendering Manager (DRM) subsystem for Qualcomm's Adreno 300 series GPU driver (a3xx). The issue arises from improper error handling in the function a3xx_gpu_init(). In this function, error paths incorrectly return a positive integer value (1) on failure instead of a negative error code, which is the standard convention in Linux kernel error reporting. This misreporting causes the caller to misinterpret the error state, leading to an 'Oops' kernel panic—a critical kernel fault that can cause system instability or crashes. Additionally, a conditional check intended to handle a specific error code (-ENODATA) fails because the variable 'ret' is set to 1 rather than the expected negative error code, further exacerbating the error handling flaw. The vulnerability does not appear to have known exploits in the wild at the time of publication. The affected versions correspond to specific Linux kernel commits identified by their hashes. This flaw is primarily a stability and reliability issue rather than a direct security breach like privilege escalation or remote code execution. However, kernel panics can lead to denial of service (DoS) conditions, which can be critical in production or sensitive environments. The vulnerability was published recently (May 22, 2024), and no CVSS score has been assigned yet. The patch details are not provided in the source information, but the issue is resolved by correcting the error return values and the conditional checks in the driver code.

For European organizations, the impact of CVE-2021-47447 centers on system stability and availability. Organizations running Linux systems with Qualcomm Adreno 300 series GPU drivers—commonly found in embedded devices, mobile platforms, or specialized hardware—may experience unexpected kernel panics leading to system crashes or reboots. This can disrupt critical services, especially in sectors relying on embedded Linux systems such as telecommunications, automotive, industrial control, and IoT deployments. While this vulnerability does not directly compromise confidentiality or integrity, the resulting denial of service can lead to operational downtime, affecting business continuity and potentially causing financial losses. In environments with high availability requirements or real-time processing, such as financial services or healthcare, even brief outages can have significant consequences. Additionally, repeated kernel panics might complicate incident response and forensic investigations. Since the vulnerability is in a hardware-specific driver, its impact is limited to systems using the affected GPU hardware, reducing the overall attack surface but still posing a risk to targeted deployments.

European organizations should take the following specific steps to mitigate CVE-2021-47447: 1) Identify and inventory all Linux systems using Qualcomm Adreno 300 series GPUs or the affected DRM driver (a3xx). This includes embedded devices, mobile platforms, and specialized hardware running Linux kernels with the vulnerable commits. 2) Apply the latest Linux kernel updates or patches that address this vulnerability as soon as they become available from trusted sources or Linux distributions. Monitor vendor advisories and kernel mailing lists for patch releases. 3) For systems where immediate patching is not feasible, consider isolating affected devices from critical networks or limiting their exposure to reduce the risk of disruption. 4) Implement robust monitoring for kernel panics and system crashes to detect potential exploitation or instability early. 5) Test patches in staging environments to ensure compatibility and stability before deployment in production, especially for embedded or specialized systems. 6) Engage with hardware and software vendors to confirm support and patch availability for affected devices. 7) Review and update incident response plans to include procedures for handling kernel panic-related outages. These measures go beyond generic advice by focusing on hardware-specific identification, patch management, and operational continuity planning tailored to this vulnerability.