This vulnerability (CVE-2025-54518) arises from improper isolation of shared resources within the CPU operation cache on AMD Zen 2-based processors, including the AMD EPYC 7002 Series. An attacker with local access and low privileges could exploit this flaw to corrupt instructions executed at a different privilege level, resulting in privilege escalation. The issue affects kernel components and the Xen hypervisor. Red Hat has released kernel patches for Red Hat Enterprise Linux 8 to mitigate this vulnerability. The CVSS v3.1 score is 7.3 (high severity) with a local attack vector, high attack complexity, and no user interaction required. The vulnerability is tracked under CWE-1189 and CWE-1220, indicating improper isolation and insufficient granularity of access control.

Successful exploitation could allow an attacker with low privileges to escalate their privileges by corrupting instructions executed at higher privilege levels, potentially compromising system confidentiality, integrity, and availability. This affects kernel and hypervisor components on affected AMD Zen 2 processors, increasing the risk of unauthorized code execution and bypassing protection mechanisms.

A security update addressing this vulnerability has been released by Red Hat for Red Hat Enterprise Linux 8. Users should apply the kernel update (e.g., kernel-4.18.0-553.153.1.el8_10 or later) as provided in Red Hat advisory RHSA-2026:50978 and reboot the system to activate the fix. Red Hat recommends treating all kernel errata as security-relevant and applying updates promptly. No alternative mitigations are specified in the advisory.