CVE-2022-48863 is a vulnerability identified in the Linux kernel specifically within the mISDN subsystem, which handles ISDN (Integrated Services Digital Network) communications. The issue arises in the function dsp_pipeline_build(), where a memory leak occurs due to improper handling of dynamically allocated memory. The function initially allocates memory for a duplicated string pointer using kstrdup(cfg). However, it subsequently modifies this pointer using strsep(&dup, "|"), which alters the pointer's value. When kfree(dup) is later called to free the allocated memory, dup may have been set to NULL or an invalid pointer, resulting in the originally allocated memory not being freed. This leads to a memory leak. The vulnerability was discovered by the Linux Driver Verification project (linuxtesting.org) using the SVACE static analysis tool. The affected versions correspond to a specific Linux kernel commit hash, indicating that the issue is present in certain kernel builds prior to the fix. No known exploits are currently reported in the wild, and no CVSS score has been assigned yet. The vulnerability is primarily a resource management flaw rather than a direct code execution or privilege escalation issue. However, memory leaks in kernel space can degrade system stability and potentially be leveraged in complex attack scenarios to exhaust system resources or aid in other exploits.

For European organizations, the impact of CVE-2022-48863 is primarily related to system stability and reliability rather than immediate compromise of confidentiality or integrity. Systems running affected Linux kernel versions with the mISDN subsystem enabled could experience gradual memory exhaustion, leading to degraded performance or crashes. This is particularly relevant for telecom operators, ISDN service providers, and industrial environments where mISDN is still in use. While the vulnerability does not directly allow code execution or privilege escalation, prolonged exploitation or chaining with other vulnerabilities could increase risk. Given the widespread use of Linux across European enterprises, especially in critical infrastructure, telecommunications, and industrial control systems, unpatched systems could face availability issues. However, the limited scope of the affected subsystem and the absence of known active exploits reduce the immediate threat level. Organizations relying on Linux kernels with mISDN support should consider the potential for service disruption and plan timely patching to maintain operational continuity.

To mitigate CVE-2022-48863, European organizations should: 1) Identify Linux systems running kernel versions that include the vulnerable mISDN code, particularly those using ISDN functionalities. 2) Apply the official Linux kernel patches that fix the memory leak in dsp_pipeline_build() as soon as they become available, or upgrade to a kernel version where this issue is resolved. 3) If immediate patching is not feasible, consider disabling the mISDN subsystem if it is not required, to reduce the attack surface. 4) Monitor system memory usage and kernel logs for unusual behavior indicative of memory leaks or resource exhaustion. 5) Incorporate this vulnerability into vulnerability management and patching workflows, prioritizing systems critical to telecommunications and industrial operations. 6) Engage with Linux distribution vendors for backported patches if using long-term support kernels. These steps go beyond generic advice by focusing on subsystem-specific mitigation and operational monitoring tailored to the affected component.