CVE-2022-21123: 
vulnerability analysis and mitigation

CVE-2022-21123 is a vulnerability related to incomplete cleanup of multi-core shared buffers in Intel processors. The vulnerability was disclosed in June 2022 and affects various Intel processor models. When successfully exploited, this vulnerability allows an authenticated user to potentially enable information disclosure via local access (NVD). The vulnerability is part of a broader set of MMIO Stale Data vulnerabilities, similar to previously published Microarchitectural Data Sampling (MDS) issues (Debian Security).

The vulnerability has been assigned a CVSS v3.1 base score of 5.5 (MEDIUM) with the vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N (NVD). The issue specifically relates to the incomplete cleanup of shared buffers in multi-core processors, which can lead to information disclosure through local access. This vulnerability is classified under CWE-459 (Incomplete Cleanup) and requires local access for exploitation (NVD).

The primary impact of this vulnerability is the potential disclosure of sensitive information. An authenticated local attacker could potentially access data from different security contexts, such as from user-space to the kernel, or between different virtual machines. The vulnerability affects various Intel processors and could lead to information leaks between different security domains (Intel Security Advisory).

Mitigation requires both software and microcode updates. Intel has released firmware updates to address these vulnerabilities (Intel Security Advisory). Various operating system vendors have released patches, including Debian which provided updates in their intel-microcode package (Debian Security). For some CPUs, the mitigations require updated microcode which may be available through system firmware ("BIOS") updates (Debian Security).

The vulnerability has been actively addressed by multiple vendors and organizations. Major Linux distributions including Debian, Fedora, and others have released security updates to address this vulnerability (Fedora Update, Debian Security). The security community has treated this as part of a broader set of processor vulnerabilities requiring coordinated response.