CVE-2026-34192: GPU System Use-After-Free Vulnerability

CVE-2026-34192 Overview

CVE-2026-34192 is a use-after-free vulnerability [CWE-416] affecting Imagination Technologies GPU drivers. A non-privileged local user can issue crafted GPU system calls that trigger an error path in the driver. This error path frees physical memory allocated for Memory Management Unit (MMU) page tables without performing required cleanup, leaving stale references that can be reused after free.

The flaw allows local attackers to compromise integrity and availability of the affected system. Exploitation requires only local code execution as an unprivileged user, with no user interaction.

Critical Impact
A local non-privileged process can corrupt GPU page table memory through a use-after-free, enabling kernel memory tampering and denial of service on affected devices.

Affected Products

Imagination Technologies GPU drivers exposing MMU page table allocation through GPU system calls
Systems integrating affected PowerVR/IMG GPU kernel components
Devices running software stacks that allow unprivileged GPU syscall access

Discovery Timeline

2026-06-19 - CVE-2026-34192 published to the National Vulnerability Database (NVD)
2026-06-22 - Last updated in NVD database

Technical Details for CVE-2026-34192

Vulnerability Analysis

The vulnerability resides in the GPU driver's MMU page table management logic. When a non-privileged process issues specific GPU system calls, the driver follows a path that allocates physical memory backing page tables for GPU translations. Under error conditions, the cleanup sequence executes out of order. The physical allocation is freed while references to it remain reachable through driver bookkeeping or hardware state.

Subsequent operations dereference the freed memory, producing a classic use-after-free condition on memory holding GPU MMU translations. Because MMU page tables map device-visible memory, corruption can be steered to influence DMA-capable mappings. This grants an attacker a primitive for kernel integrity violation and induced instability.

Root Cause

The root cause is improper resource cleanup on an error path. The driver releases the physical backing memory before invalidating MMU references and clearing internal pointer state. The error handler does not respect the established acquire/release ordering used by the success path.

Attack Vector

The attack vector is local. An attacker executes code as a non-privileged user on the target device and issues malformed or sequenced GPU system calls designed to drive the driver into the faulty error path. No user interaction is required. The vulnerability cannot be triggered remotely without prior local code execution.

No verified public proof-of-concept code is currently associated with this CVE. Refer to the Imagination Technologies Vulnerability Report for vendor technical details.

Detection Methods for CVE-2026-34192

Indicators of Compromise

Unexpected GPU driver kernel oops, panics, or watchdog resets referencing MMU or page table routines
Repeated GPU reset events or device hangs originating from unprivileged user processes
Kernel logs showing slab corruption or KASAN use-after-free reports in GPU driver modules

Detection Strategies

Monitor kernel ring buffer (dmesg) for warnings emitted by the GPU driver during MMU teardown
Hunt for non-privileged processes issuing high volumes of GPU ioctl or syscall sequences against the GPU device node
Correlate userland process crashes with subsequent GPU driver fault traces in the same time window

Monitoring Recommendations

Enable kernel address sanitizer (KASAN) or equivalent allocator hardening in test environments to surface UAF conditions
Forward kernel logs to a centralized logging or SIEM platform for retention and pattern analysis
Alert on repeated access to GPU device nodes by processes outside the expected graphics or compute workload profile

How to Mitigate CVE-2026-34192

Immediate Actions Required

Apply vendor-supplied GPU driver updates from Imagination Technologies as soon as they are available for your platform
Inventory devices using affected GPU drivers and prioritize multi-tenant or shared systems for patching
Restrict access to GPU device nodes to trusted user groups where operationally feasible

Patch Information

Consult the Imagination Technologies Vulnerability Report for the authoritative list of fixed driver versions and integration guidance for downstream vendors. Device OEMs and Linux distribution maintainers should ship the corrected driver in their next security update.

Workarounds

Limit untrusted local code execution on affected devices until patches are deployed
Tighten permissions on GPU device files (for example, /dev/dri/* or vendor-specific nodes) to restrict unprivileged syscall access
Disable or remove GPU compute workloads from shared systems where unprivileged users can run arbitrary code

bash

# Configuration example: restrict GPU device node access to the video group
sudo chown root:video /dev/dri/renderD128
sudo chmod 660 /dev/dri/renderD128
# Verify only intended users are members of the video group
getent group video