CVE-2022-0330: Linux Kernel i915 Privilege Escalation

CVE-2022-0330 Overview

A random memory access flaw was found in the Linux kernel's GPU i915 kernel driver functionality in the way a user may run malicious code on the GPU. This flaw allows a local user to crash the system or escalate their privileges on the system. The vulnerability exists due to improper preservation of permissions (CWE-281) within the Intel i915 graphics driver, which is widely used in Intel integrated graphics hardware.

Critical Impact

Local privilege escalation and system crash capabilities affecting Linux kernel systems with Intel i915 GPU drivers, impacting enterprise Linux distributions, virtualization platforms, and NetApp storage appliances.

Affected Products

• Linux Kernel (versions prior to 5.17 and including 5.17-rc1)
• Red Hat Enterprise Linux 7.x and 8.x (including Desktop, Server, Workstation, and EUS variants)
• Red Hat Virtualization 4.0 and Virtualization Host 4.0
• Fedora 34 and 35
• NetApp H-Series Storage Appliances (H300s, H500s, H700s, H300e, H500e, H700e, H410s, H410c)

Discovery Timeline

• 2022-03-25 - CVE-2022-0330 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2022-0330

Vulnerability Analysis

The vulnerability resides in the Linux kernel's i915 graphics driver, which handles Intel integrated GPU hardware. The flaw stems from improper preservation of permissions when processing GPU commands, allowing unauthorized memory access patterns that can be exploited by local users. When malicious code is executed on the GPU, the driver fails to properly validate memory access boundaries and permission contexts, resulting in random memory access that can be weaponized for privilege escalation or denial of service attacks.

The attack requires local access to the system, meaning an attacker must already have some level of access to the target machine. However, once local access is obtained, exploitation can lead to complete system compromise through kernel-level privilege escalation, or targeted denial of service through system crashes.

Root Cause

The root cause is classified as CWE-281 (Improper Preservation of Permissions). The i915 driver does not adequately preserve or check permission contexts when handling GPU memory operations. This allows user-space code running on the GPU to access memory regions that should be protected, bypassing the intended isolation between user-space and kernel-space memory. The permission preservation failure occurs during the execution of GPU commands, where the driver fails to maintain proper memory access controls throughout the command processing lifecycle.

Attack Vector

The attack vector is local, requiring the attacker to have authenticated access to the target system. The exploitation path involves:

1. A local user submits specially crafted GPU commands through the i915 driver interface
2. The driver processes these commands without properly preserving permission contexts
3. The malicious GPU code gains access to arbitrary kernel memory locations
4. The attacker can then either crash the system (denial of service) or manipulate kernel structures to escalate privileges

The attack complexity is low and does not require user interaction, making it particularly dangerous in multi-tenant environments or systems where local user access is available to potentially untrusted parties.

Detection Methods for CVE-2022-0330

Indicators of Compromise

• Unexpected system crashes or kernel panics involving the i915 driver module
• Unusual GPU memory allocation patterns or errors in kernel logs related to drm/i915
• Evidence of privilege escalation attempts from low-privilege user accounts
• Kernel oops messages referencing i915 driver functions in system logs

Detection Strategies

• Monitor kernel logs (dmesg, /var/log/kern.log) for i915 driver errors or warnings indicating memory access violations
• Implement auditd rules to track access to GPU device files (/dev/dri/*) from unprivileged processes
• Deploy kernel-level monitoring to detect anomalous memory access patterns in the graphics subsystem
• Use SentinelOne's kernel-level monitoring capabilities to detect exploitation attempts targeting GPU drivers

Monitoring Recommendations

• Enable kernel auditing for DRM (Direct Rendering Manager) subsystem events
• Configure alerting for unexpected i915 module errors or kernel panics
• Monitor for unusual patterns of GPU resource utilization from non-graphical processes
• Review system logs regularly for signs of privilege escalation attempts following GPU-related activities

How to Mitigate CVE-2022-0330

Immediate Actions Required

• Apply the latest kernel updates from your Linux distribution vendor immediately
• Review and restrict local user access to systems with Intel i915 graphics hardware
• Consider disabling or limiting access to GPU functionality for untrusted local users where feasible
• Implement defense-in-depth measures including SELinux/AppArmor policies to contain potential exploitation

Patch Information

Patches have been released by major Linux distributions and the upstream Linux kernel project. Red Hat has addressed this vulnerability across multiple Enterprise Linux versions including RHEL 7.x and 8.x variants. Fedora 34 and 35 users should update to the latest kernel packages. NetApp has released firmware updates for affected H-Series storage appliances.

For detailed patch information, consult the following resources:

• Red Hat Bugzilla Report
• NetApp Security Advisory
• OpenWall OSS-Security Discussion

Workarounds

• Restrict local user access to the system, limiting the attack surface for this local-only vulnerability
• Use kernel module blacklisting to disable the i915 driver if Intel graphics are not required for system operation
• Implement mandatory access control policies (SELinux, AppArmor) to limit GPU device access
• Consider deploying systems without Intel integrated graphics in high-security environments until patches are applied

# Blacklist i915 driver if Intel GPU is not required
echo "blacklist i915" >> /etc/modprobe.d/blacklist.conf
update-initramfs -u

# Restrict access to DRI devices (adjust permissions as needed)
chmod 660 /dev/dri/*
chown root:video /dev/dri/*