CVE-2026-53202: Linux Kernel Intel VPU Stack Buffer Overflow (CVSS 7.8)

Technical summary

CVE-2026-53202 is a signed integer truncation vulnerability in the Linux kernel's accel/ivpu (Intel VPU acceleration) subsystem. The vulnerability occurs in IPC (Inter-Process Communication) receive handling where a firmware-supplied data_size parameter is improperly cast from unsigned to signed integer before being passed to min_t(int, ...). When data_size ≥ 0x80000000 (2GB), the signed cast causes integer wraparound, resulting in a negative value. This negative value is then used in min_t(), which can cause the function to select an unexpectedly large buffer size, leading to memcpy operations that exceed the allocated stack buffer boundaries. The fix involves removing the explicit signed integer cast and using min() with both unsigned values, allowing proper type handling without unsafe truncation.

Business impact

Organizations running affected Linux kernels on systems with Intel VPU hardware face a localized privilege escalation and denial-of-service risk. While exploitation requires local access and user-level privileges (PR:L per CVSS), a successful attack could crash the kernel or potentially allow code execution with kernel privileges. For enterprises deploying Intel VPU accelerators in AI/ML workloads, container orchestration, or specialized computing environments, this represents a moderate-to-high operational risk, particularly in multi-tenant scenarios where multiple users share access to VPU resources.

Affected systems

The vulnerability affects the Linux kernel accel/ivpu driver, which provides hardware acceleration support for Intel VPU devices. Any Linux system running a vulnerable kernel version with VPU support enabled is at risk. The vulnerability is specific to systems with Intel VPU hardware; systems without this hardware or with the VPU subsystem disabled are not affected. Verify your kernel version and configuration against vendor advisories to determine exposure.

Exploitability

Exploitation requires local system access (AV:L) and is not network-exploitable. An attacker must have user-level privileges (PR:L) to trigger the vulnerable code path by sending specially crafted firmware data or IPC messages to the VPU driver. No special user interaction is required (UI:N). The attack surface is limited to systems where users have local access and the VPU driver is active; however, the ease of triggering the integer truncation via normal IPC operations makes it relatively straightforward for a privileged local process to exploit. CVSS 7.8 (HIGH) reflects high impact (confidentiality, integrity, and availability) balanced against local-only access requirements.

Remediation

Remediation requires patching the Linux kernel to a version where the signed integer truncation has been fixed. The fix changes the min_t(int, ...) call to min() without explicit casting, ensuring both parameters remain unsigned and preventing wraparound. Users should apply the latest stable kernel updates from their distribution or kernel.org. Affected systems should prioritize patching if VPU hardware is enabled and user access is multi-tenant or untrusted; systems with dedicated, single-user VPU deployments face lower immediate risk.

Patch guidance

Obtain patched kernel versions from your Linux distribution's security repository or kernel.org. The fix has been integrated into the mainline kernel; verify the specific version number from your vendor's advisory, as backport availability varies across distributions. After patching, reboot the system to load the fixed kernel. For systems unable to reboot immediately, consider disabling VPU driver modules (modprobe -r ivpu) as a temporary mitigation, though this will disable VPU acceleration capabilities.

Detection guidance

Monitor kernel logs for unexpected crashes or panics originating from ivpu or VPU-related subsystem warnings, which may indicate exploitation attempts. On systems with VPU drivers loaded, audit user-level process interactions with /dev/ivpu or VPU IPC channels using strace or seccomp monitoring. Check running kernel version with 'uname -r' and verify against patched versions from your vendor. Intrusion detection systems should monitor for abnormal memory access patterns or stack buffer anomalies in VPU driver execution contexts, though host-based detection may be limited given the local-only attack vector.

Why prioritize this

Although this vulnerability requires local access, the combination of HIGH CVSS score (7.8), full system impact (CIA), and the relative ease of exploitation via IPC messages warrants prioritization in kernel patching cycles. Organizations with multi-tenant systems, shared computing clusters, or containerized environments where users have local access should prioritize immediately. Single-user systems or those with VPU disabled can address this in routine maintenance windows.

Risk score, explained

The CVSS 3.1 score of 7.8 (HIGH) reflects: local-only attack vector (reducing network risk), user-level privilege requirement (limiting blast radius), but high impact across confidentiality, integrity, and availability (kernel code execution, system crash). The score appropriately balances the severity of potential impact (kernel compromise) against the limited but realistic exploitability in multi-user or cloud-native environments.

Frequently asked questions