CVE-2022-48642: 
Linux Kernel vulnerability analysis and mitigation

CVE-2022-48642 is a vulnerability in the Linux kernel's netfilter component, specifically affecting the nf_tables functionality. The issue was discovered in the nf_tables_addchain() function where percpu memory for chain stats started leaking since commit 3bc158f8d0330f0a when nft_chain_offload_priority() returned an error. The vulnerability affects Linux kernel versions from 5.3 through 5.10.146, 5.11 through 5.15.71, 5.16 through 5.19.12, and various release candidates of version 6.0 (NVD).

The vulnerability is classified as a Missing Release of Memory after Effective Lifetime (CWE-401) issue. It has been assigned a CVSS v3.1 Base Score of 5.5 (Medium) with the vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H, indicating local access requirements and potential high impact on availability (NVD).

The vulnerability results in a memory leak in the Linux kernel's netfilter subsystem, specifically affecting per-CPU memory allocation for chain statistics. This can lead to resource exhaustion and potential system instability (NVD).

The vulnerability requires local access with low complexity and low privileges to exploit. No user interaction is needed for exploitation, though the attack requires local access to the system (NVD).

The vulnerability has been fixed through a patch that properly frees percpu memory when an error occurs. The fix has been implemented in various Linux kernel versions, and affected distributions have released updates. For example, Debian has marked it as fixed in versions 5.10.223-1 for bullseye and 6.1.123-1 for bookworm (Debian).