CVE-2021-47492

A flaw was found in the Linux kernel's Transparent Huge Pages (THP) memory management subsystem. A local user can exploit this vulnerability to cause a kernel panic, resulting in a Denial of Service (DoS). This issue occurs when the kernel attempts to collapse file-backed memory pages into huge pages on filesystems such as XFS without properly checking if a page is actively undergoing writeback to storage.

This vulnerability is rated as Moderate impact for Red Hat Enterprise Linux because exploitation requires local system access and is limited to causing a denial of service via a kernel panic, without impacting data confidentiality or integrity. The issue depends on specific timing when the memory management subsystem collapses file-backed pages on XFS filesystems while those pages are actively undergoing disk writeback. Because triggering the condition is non-deterministic and cannot be leveraged for privilege escalation or code execution, the overall risk is confined to system availability.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.