CVE-2026-53202: Linux Kernel Buffer Overflow Vulnerability

CVE-2026-53202 Overview

CVE-2026-53202 is a Linux kernel vulnerability in the accel/ivpu driver, which supports Intel Versatile Processing Unit (VPU) accelerators. The flaw resides in the inter-process communication (IPC) receive path, where firmware-supplied data_size values are improperly cast to a signed integer before use in a min_t() macro. Large unsigned values at or above 0x80000000 become negative after the cast, triggering unsigned wraparound logic that produces oversized memcpy() lengths. The result is a stack buffer overflow driven by attacker-influenced firmware data. Maintainers fixed the issue by replacing min_t(int, ...) with min(), preserving unsigned semantics across both operands.

Critical Impact
A signed integer truncation in the ivpu IPC receive routine can cause a stack-based buffer overflow when crafted firmware data is processed, leading to kernel memory corruption.

Affected Products

Linux kernel accel/ivpu driver (Intel VPU accelerator support)
Kernel branches referenced by upstream stable commits 2821bf2, 45cb105, 4788556, and d9faef5
Distributions shipping the affected kernel revisions prior to backport

Discovery Timeline

2026-06-25 - CVE-2026-53202 published to NVD
2026-06-25 - Last updated in NVD database

Technical Details for CVE-2026-53202

Vulnerability Analysis

The accel/ivpu driver implements an IPC channel between the host kernel and Intel VPU firmware. On the receive path, the driver reads a data_size field provided by the firmware and bounds it against a destination buffer length using the min_t(int, ...) macro. Because min_t performs a typed comparison, both operands are cast to int. Firmware-supplied data_size values of 0x80000000 or higher are unsigned by origin but become negative after the cast. The kernel then treats the negative value as the smaller operand, returning it from min_t().

When the returned length is subsequently passed to memcpy(), which expects a size_t, the negative integer is sign-extended and reinterpreted as an extremely large unsigned value. The resulting copy writes far beyond the destination stack buffer, producing kernel stack corruption. This falls under Numeric Truncation Error and Stack-based Buffer Overflow categories.

Root Cause

The root cause is the explicit int type argument to min_t() in the IPC receive handler. Both compared values are unsigned by design, so the signed cast is unnecessary and introduces a truncation defect. The fix changes the macro to min(), which derives its type from the unsigned operands and removes the sign conversion entirely.

Attack Vector

Exploitation requires the ability to influence the data_size field delivered by the VPU firmware to the host driver. An attacker capable of supplying or tampering with firmware messages, or a compromised firmware image, can craft a data_size value at or above 0x80000000. The driver then performs an oversized memcpy() into a stack buffer in kernel context, corrupting adjacent kernel memory and potentially enabling privilege escalation or denial of service.

No public proof-of-concept code is available. Refer to the upstream commits (Kernel Git Commit 2821bf2, Kernel Git Commit 45cb105, Kernel Git Commit 4788556, and Kernel Git Commit d9faef5) for the precise code change.

Detection Methods for CVE-2026-53202

Indicators of Compromise

Unexpected kernel oops or panic traces referencing ivpu_ipc symbols or memcpy from the IPC receive path
Stack protector (CONFIG_STACKPROTECTOR) reports identifying corruption in ivpu driver frames
Anomalous Intel VPU device resets or firmware reload events in dmesg

Detection Strategies

Inventory running kernel versions and confirm whether the accel/ivpu driver is loaded on systems with Intel VPU hardware
Audit kernel logs for ivpu warnings, KASAN reports, or stack canary violations indicating memory corruption
Track firmware integrity by validating signatures and versions of VPU firmware images loaded at boot

Monitoring Recommendations

Forward kernel ring buffer and journald events from VPU-enabled hosts to a centralized log pipeline for correlation
Alert on driver reload sequences, MCE events, or unexpected reboots on systems exposing the ivpu interface
Monitor package management activity to verify that kernel updates carrying the upstream fix are deployed across the fleet

How to Mitigate CVE-2026-53202

Immediate Actions Required

Apply the upstream kernel patches referenced by commits 2821bf2, 45cb105, 4788556, and d9faef5 once distributed by your distribution vendor
Restrict physical and administrative access to systems containing Intel VPU accelerators while patches are pending
Validate that only signed, vendor-supplied VPU firmware is permitted to load through request_firmware() paths

Patch Information

The fix replaces min_t(int, ...) with min() in the ivpu IPC receive routine, eliminating the signed cast and preserving unsigned semantics for both operands. Patches are available in the upstream Linux stable tree via the referenced kernel.org commits. Distribution kernels (Red Hat, SUSE, Ubuntu, Debian, and others) will integrate the fix through their standard stable backport process; consult vendor security trackers for build-specific availability.

Workarounds

Unload the intel_vpu module on hosts that do not require VPU acceleration using modprobe -r intel_vpu
Blacklist the driver until a patched kernel is installed by adding blacklist intel_vpu to /etc/modprobe.d/
Disable VPU functionality in firmware or BIOS where the option is exposed to remove the attack surface entirely

bash

# Configuration example
# Blacklist the ivpu driver until a patched kernel is deployed
echo 'blacklist intel_vpu' | sudo tee /etc/modprobe.d/disable-ivpu.conf
sudo modprobe -r intel_vpu
sudo update-initramfs -u