CVE-2024-36881

A flaw was found in the userfaultfd subsystem of the Linux kernel. This issue may result in a denial of service (DoS) due to improper memory cleanup. When an application closes a userfaultfd file descriptor without explicitly unregistering write-protected memory ranges, the kernel fails to reset write-protection flags on page table entries. A local user can exploit this behavior to leave stale memory flags, triggering kernel warning traces and potential system instability.

This vulnerability is rated as having a Moderate impact because exploiting it requires local access to interact with the userfaultfd interface, constraining potential consequences to a localized denial of service rather than code execution or arbitrary memory corruption. On standard Red Hat Enterprise Linux installations, unprivileged user access to userfaultfd is disabled by default via system controls, significantly reducing attack surface exposure in typical environments. Consequently, triggering this condition requires either elevated privileges (such as CAP_SYS_PTRACE) or an explicitly loosened configuration, limiting overall risk to production deployments.

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.