CVE-2023-53084: 
Linux Kernel vulnerability analysis and mitigation

CVE-2023-53084 is a vulnerability discovered in the Linux kernel, specifically in the drm/shmem-helper component. The vulnerability was published on May 2, 2025, and involves an error in the reference handling within the drmgemshmem_mmap() function (NVD).

The vulnerability occurs in the drmgemshmem_mmap() function where it doesn't properly own the reference in the error code path. This implementation flaw results in the dma-buf shmem GEM object being prematurely freed, which subsequently leads to a use-after-free condition. The vulnerability has been assigned a CVSS v3.1 base score of 5.5 with the vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H, indicating a moderate severity level (Red Hat).

The vulnerability primarily affects the availability of the system through the premature freeing of memory objects. The CVSS scoring indicates that while there is no impact on confidentiality or integrity, there is a high impact on availability, requiring local access and low privileges to exploit (Red Hat).

Several Linux distributions have released fixes for this vulnerability. Ubuntu has addressed the issue in version 5.15.0-79.86 for 22.04 LTS (jammy) and other affected versions. Red Hat Enterprise Linux 9 has deferred the fix for both kernel and kernel-rt packages. Debian has fixed the vulnerability in multiple versions: bullseye (5.10.234-1), bookworm (6.1.137-1), and trixie/sid (6.12.27-1) (Ubuntu, Debian).