CVE-2023-52936 is a vulnerability identified in the Linux kernel, specifically within the kernel's interrupt request (IRQ) domain management code located in irqdomain.c. The issue arises from improper handling of the debugfs_lookup() function, which is used to access debug filesystem entries. The vulnerability is a memory leak caused by the failure to call dput() on the result of debugfs_lookup(), which is necessary to decrement the reference count and release the associated memory. Without this call, memory allocated during the lookup accumulates over time, leading to a gradual memory leak. The patch resolves this by replacing the debugfs_lookup() call and manual dput() with debugfs_lookup_and_remove(), a function that encapsulates the entire logic and ensures proper cleanup. This fix prevents the memory leak from occurring. Although the vulnerability does not directly allow code execution or privilege escalation, the memory leak can degrade system performance and stability, especially on systems with long uptimes or heavy debugfs usage. The affected versions are specific Linux kernel commits identified by the hash 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2. There are no known exploits in the wild at this time, and no CVSS score has been assigned. The vulnerability is primarily a resource management flaw rather than a direct security breach vector.

For European organizations, the impact of CVE-2023-52936 is primarily related to system reliability and availability rather than direct compromise of confidentiality or integrity. Systems running vulnerable Linux kernel versions that heavily utilize debugfs, such as servers used for development, debugging, or embedded systems with long uptimes, may experience gradual memory exhaustion. This can lead to degraded performance, increased system crashes, or forced reboots, potentially disrupting critical services. Organizations relying on Linux-based infrastructure for critical operations, including cloud providers, telecom operators, and industrial control systems, could face operational interruptions if the vulnerability is not addressed. However, since exploitation does not grant attackers elevated privileges or direct access, the risk of data breaches or system takeover is low. The absence of known exploits reduces immediate threat urgency but does not eliminate the need for remediation to maintain system health and prevent denial-of-service conditions caused by resource depletion.

To mitigate CVE-2023-52936, European organizations should prioritize updating their Linux kernels to versions that include the fix replacing debugfs_lookup() with debugfs_lookup_and_remove(). Kernel updates should be applied promptly, especially on systems with long uptimes or those used for debugging and development purposes. System administrators should audit their environments to identify any custom or legacy kernels that might still be vulnerable. Additionally, monitoring memory usage patterns on critical Linux hosts can help detect abnormal memory growth indicative of this leak. For embedded or specialized systems where immediate kernel upgrades are challenging, consider limiting debugfs usage or implementing periodic system restarts as a temporary workaround. Organizations should also ensure that their patch management processes include Linux kernel updates and verify that security advisories are tracked continuously. Since no authentication or user interaction is required to trigger the leak, ensuring that all Linux hosts are patched is essential to prevent gradual degradation.