CVE-2023-53112 is a vulnerability identified in the Linux kernel's Intel i915 graphics driver, specifically within the drm/i915/sseu (Slice/Subslice/EU) subsystem. The issue arises from an array-index-out-of-bounds access in the max_subslices array within the eu_mask structure. The vulnerability was introduced following a commit (bc3c5e0809ae) that altered how the EU mask is stored internally, inadvertently allowing the gen11_sseu_info_init() function to set up to 8 sub-slices in certain hardware configurations, exceeding the originally defined maximum of 6 sub-slices (GEN_MAX_SS_PER_HSW_SLICE). This discrepancy leads to an out-of-bounds access when the code attempts to index beyond the allocated array size, which is detected by the Undefined Behavior Sanitizer (UBSAN) during runtime on affected hardware such as laptops with Gen 11 Intel i915 graphics cards. The root cause is a mismatch between the array size reserved for sub-slices and the actual number of sub-slices the driver attempts to handle. The fix involves increasing the reserved slots for max_subslices in the eu_mask struct to accommodate up to 8 sub-slices, preventing out-of-bounds memory access. While this vulnerability does not have known exploits in the wild, it represents a memory safety flaw that could potentially lead to system instability or denial of service if triggered. The vulnerability is specific to certain Intel GPU hardware configurations running Linux kernel versions that include the problematic commit and prior to the patch. No CVSS score has been assigned yet, and no evidence suggests privilege escalation or remote code execution directly from this flaw, but the out-of-bounds access could be leveraged in complex attack chains or cause kernel crashes.

For European organizations, the impact of CVE-2023-53112 primarily concerns systems running Linux with Intel Gen 11 i915 graphics hardware, which is common in many enterprise laptops and desktops, including popular models like Dell XPS series. The vulnerability could lead to kernel crashes or system instability, potentially causing denial of service conditions. This can disrupt business operations, especially in environments relying on Linux-based workstations or servers with integrated Intel graphics. While the vulnerability does not directly enable code execution or privilege escalation, the instability could be exploited by local attackers or malicious software to degrade system reliability or facilitate further attacks. Organizations in sectors with high reliance on Linux workstations, such as software development, research institutions, and technology companies, may be more affected. Additionally, critical infrastructure or industrial control systems using affected hardware and Linux kernels could face operational risks. The absence of known exploits reduces immediate risk, but unpatched systems remain vulnerable to accidental crashes or targeted local attacks.

To mitigate CVE-2023-53112, European organizations should: 1) Apply the latest Linux kernel updates that include the patch fixing the max_subslices array bounds issue. This patch increases the reserved array size to prevent out-of-bounds access. 2) Identify and inventory systems using Intel Gen 11 i915 graphics hardware and verify kernel versions to prioritize patch deployment. 3) For environments where immediate patching is challenging, consider temporarily disabling the i915 driver or using kernel boot parameters to limit GPU features, though this may reduce graphics performance. 4) Monitor system logs for UBSAN or kernel warnings related to i915 or drm subsystems that could indicate attempts to trigger the vulnerability. 5) Implement strict local user access controls to limit untrusted users from executing code or processes that could exploit kernel vulnerabilities. 6) Engage with hardware vendors and Linux distribution maintainers to ensure timely updates and guidance. 7) Incorporate this vulnerability into vulnerability management and patching workflows to maintain ongoing security posture.