CVE-2021-47654 is a vulnerability identified in the Linux kernel, specifically related to the Landlock security module sample code. The issue arises from a memory leak in the handling of the 'path_list' data structure within the sandboxer.c file. According to the Clang static analyzer, the 'path_list' pointer is allocated memory in the parse_path() function but is never freed, leading to a potential memory leak. This flaw does not directly result in code execution or privilege escalation but could cause resource exhaustion over time if exploited in a targeted manner. The vulnerability is located in sample code for Landlock, which is a Linux security module designed to provide sandboxing capabilities by restricting filesystem access. The affected versions are identified by a specific commit hash (ba84b0bf5a164f0f523656c1e37568c30f3f3303), indicating that this issue is tied to a particular state of the Linux kernel source code. There are no known exploits in the wild at this time, and no CVSS score has been assigned. The vulnerability was published on February 26, 2025, and while it is a memory leak, it does not appear to directly compromise confidentiality, integrity, or availability in a straightforward manner. However, memory leaks can degrade system performance and stability, especially in long-running or resource-constrained environments. The lack of a patch link suggests that remediation may require manual code updates or kernel upgrades once a fix is released.

For European organizations, the impact of CVE-2021-47654 is primarily related to system stability and resource management rather than direct security breaches. Organizations running Linux kernels that include the vulnerable Landlock sample code could experience gradual memory consumption increases, potentially leading to degraded performance or denial of service conditions if the leak is triggered repeatedly or under heavy load. This could affect critical infrastructure, cloud service providers, and enterprises relying on Linux-based systems for their operations. While the vulnerability does not currently have known exploits, the presence of a memory leak in security sandboxing code could undermine trust in the sandbox's reliability, potentially impacting security posture indirectly. European organizations with high reliance on Linux for secure containerization, sandboxing, or application isolation should be aware of this issue. The impact is more pronounced in environments where Landlock is actively used or tested, such as development or security-focused deployments. Given the absence of direct exploitation vectors, the immediate risk is low, but the potential for future exploitation or system instability warrants attention.

To mitigate the risks associated with CVE-2021-47654, European organizations should: 1) Monitor Linux kernel updates and apply patches promptly once an official fix for this memory leak is released. 2) Review and audit the use of Landlock sandboxing in their environments, ensuring that any custom or sample code is scrutinized for memory management issues. 3) Employ runtime monitoring tools to detect abnormal memory usage patterns that could indicate leaks, enabling proactive response before system degradation occurs. 4) Consider disabling or limiting the use of Landlock sample code in production environments until the vulnerability is resolved, especially if the sandbox is not critical to operations. 5) Engage with Linux kernel maintainers or security mailing lists to stay informed about developments related to this vulnerability and any emerging exploit techniques. 6) For organizations developing or deploying custom sandboxing solutions based on Landlock, conduct thorough static and dynamic code analysis to identify and fix similar memory management issues.