CVE-2026-22167: GPU Privilege Escalation Vulnerability

CVE-2026-22167 Overview

CVE-2026-22167 is a local privilege escalation vulnerability affecting Imagination Technologies GPU drivers. A non-privileged user can issue improper Graphics Processing Unit (GPU) system calls that force the GPU to write to arbitrary physical memory pages. The flaw is classified under [CWE-119] for improper restriction of operations within the bounds of a memory buffer.

Exploitation can corrupt kernel data structures and driver memory, altering the behavior of code running on the platform. The attack first targets restricted internal GPU buffers, producing a second-order effect that yields arbitrary physical memory corruption.

Critical Impact

A local, low-privileged attacker can corrupt kernel memory through crafted GPU system calls, leading to privilege escalation, kernel compromise, and full loss of host integrity.

Affected Products

• Imagination Technologies GPU drivers (see Imagination Technologies GPU Driver Vulnerabilities)
• Platforms shipping affected PowerVR/IMG GPU kernel drivers
• Devices exposing the GPU device interface to non-privileged users

Discovery Timeline

• 2026-05-01 - CVE-2026-22167 published to the National Vulnerability Database (NVD)
• 2026-05-06 - Last updated in NVD database

Technical Details for CVE-2026-22167

Vulnerability Analysis

The vulnerability lives at the boundary between user-mode applications and the GPU kernel driver. A non-privileged process invokes GPU system calls (ioctls) with crafted parameters that the driver fails to validate against expected memory boundaries. The driver then programs the GPU to perform Direct Memory Access (DMA) writes outside of buffers it legitimately owns.

Because the GPU operates on physical addresses through its Memory Management Unit (MMU), uncontrolled writes bypass standard CPU-side memory protections. The attacker manipulates internal GPU buffers first, and those tainted buffers then cause writes to arbitrary physical memory pages used by the kernel and other drivers.

Successful exploitation results in confidentiality, integrity, and availability impact on the affected host. Attack complexity is low and no user interaction is required, though the attacker must already hold a local user account.

Root Cause

The root cause is improper restriction of operations within the bounds of a memory buffer in the GPU driver's system call handlers. Parameter validation does not adequately constrain the physical pages or buffer descriptors that the GPU is instructed to access. This permits the GPU command stream to reference memory regions it should never touch.

Attack Vector

The attack vector is local. An attacker delivers malicious software, or operates as a non-privileged user, on a system equipped with a vulnerable Imagination GPU driver. The exploit issues a sequence of GPU ioctls that submit command buffers referencing invalid or attacker-chosen memory regions. The GPU executes those commands and corrupts kernel pages, enabling privilege escalation or persistent rootkit-style implants.

No verified public proof-of-concept code is available. Refer to the Imagination Technologies GPU Driver Vulnerabilities advisory for vendor-specific technical details.

Detection Methods for CVE-2026-22167

Indicators of Compromise

• Unexpected kernel panics, oopses, or memory corruption traces originating from GPU driver modules
• Non-privileged processes opening the GPU device node and submitting unusually large or malformed command buffers
• Anomalous GPU page-fault or MMU error counters reported in kernel logs
• New or unsigned kernel modules appearing after a session that exercised the GPU device interface

Detection Strategies

• Audit ioctl calls against GPU device nodes such as /dev/dri/* and vendor-specific PowerVR device files for non-standard parameter patterns
• Correlate GPU driver kernel log messages with subsequent privilege changes or suspicious process executions
• Apply behavioral rules that flag unprivileged processes performing repeated GPU memory mapping or buffer submission operations outside known-good applications

Monitoring Recommendations

• Forward kernel ring buffer (dmesg) and auditd syscall logs to a centralized analytics platform for retention and correlation
• Monitor process lineage for non-privileged binaries that suddenly gain elevated capabilities after interacting with the GPU subsystem
• Track integrity of kernel modules and read-only kernel data structures using runtime attestation where available

How to Mitigate CVE-2026-22167

Immediate Actions Required

• Inventory all systems running Imagination Technologies GPU drivers, including embedded, mobile, and SoC-based platforms
• Apply the vendor-supplied driver update referenced in the Imagination Technologies GPU Driver Vulnerabilities advisory as soon as it is available for your platform
• Restrict local access on multi-user systems and remove untrusted users from groups that can access GPU device nodes

Patch Information

Imagination Technologies has published a coordinated advisory at Imagination Technologies GPU Driver Vulnerabilities. System integrators and Original Equipment Manufacturers (OEMs) must rebuild and distribute kernel modules incorporating the vendor fix. Validate driver versions on each platform after deployment because GPU drivers are typically delivered through device firmware or vendor BSP channels rather than upstream OS package repositories.

Workarounds

• Tighten Discretionary Access Control (DAC) permissions on GPU device nodes to limit which users and groups can issue GPU ioctls
• Disable or remove unnecessary GPU compute interfaces on systems that do not require GPU acceleration for non-privileged workloads
• Apply Mandatory Access Control (MAC) policies, such as SELinux or AppArmor profiles, to confine processes that legitimately need GPU access

# Configuration example: restrict GPU device node access to a trusted group
sudo groupadd gpu-trusted
sudo chown root:gpu-trusted /dev/dri/renderD128
sudo chmod 0660 /dev/dri/renderD128
# Verify which users currently have access
getfacl /dev/dri/renderD128