CVE-2021-47031 is a medium-severity vulnerability identified in the Linux kernel, specifically within the mt76 wireless driver for the mt7921 chipset. The issue is a memory leak occurring in the function mt7921_coredump_work. A memory leak in kernel space can lead to gradual exhaustion of system memory resources, potentially degrading system performance or causing instability over time. This vulnerability does not directly impact confidentiality or integrity but affects availability due to resource depletion. The vulnerability requires network access (AV:N), low attack complexity (AC:L), and privileges (PR:L) but does not require user interaction (UI:N). The scope is unchanged (S:U), meaning the vulnerability affects only the vulnerable component without impacting other system components. The CVSS score is 4.3, reflecting a medium severity level. There are no known exploits in the wild, and no patches are linked in the provided data, though the description indicates the issue has been fixed. The underlying weakness is classified as CWE-401, which corresponds to improper release of memory, a common cause of memory leaks. The affected versions are identified by specific git commit hashes, indicating the vulnerability is present in certain Linux kernel builds prior to the fix. Overall, this vulnerability is a resource management flaw in a wireless driver component of the Linux kernel that could lead to denial of service through memory exhaustion if exploited over time.

For European organizations, the impact of CVE-2021-47031 primarily concerns systems running Linux kernels with the mt76 wireless driver supporting the mt7921 chipset. Organizations relying on Linux-based infrastructure with wireless connectivity using this chipset may experience degraded system performance or potential denial of service conditions due to memory leaks. This could affect servers, network appliances, or endpoint devices that use the affected wireless hardware. While the vulnerability does not allow for privilege escalation or data compromise, the availability impact could disrupt critical services, especially in environments where uptime and reliability are essential, such as telecommunications, financial services, healthcare, and public sector infrastructure. The medium severity and absence of known exploits reduce immediate risk, but unpatched systems remain vulnerable to potential exploitation through sustained network activity targeting the wireless driver. European organizations with large-scale deployments of Linux systems using this hardware should prioritize remediation to avoid operational disruptions.

1. Apply the official Linux kernel updates that include the fix for CVE-2021-47031 as soon as they become available from trusted sources or Linux distribution vendors. 2. Identify and inventory all systems using the mt7921 wireless chipset and verify the kernel version and driver status to assess exposure. 3. Where immediate patching is not feasible, consider disabling the mt76 wireless driver or the affected wireless hardware temporarily to mitigate risk. 4. Monitor system memory usage on affected devices for unusual increases that could indicate exploitation attempts or memory leaks. 5. Implement network segmentation and access controls to limit exposure of vulnerable wireless interfaces to untrusted networks. 6. Maintain up-to-date intrusion detection and prevention systems capable of identifying anomalous wireless traffic patterns that might exploit driver vulnerabilities. 7. Engage with Linux distribution security advisories and subscribe to relevant vulnerability feeds to stay informed about patches and exploit developments related to this vulnerability.