CVE-2026-23791: Samsung Exynos DPU Privilege Escalation Flaw

CVE-2026-23791 Overview

CVE-2026-23791 is an out-of-bounds write vulnerability in the Display Processing Unit (DPU) driver of multiple Samsung Exynos mobile processors. The flaw stems from missing input length validation during color mode Look-Up Table (LUT) parsing. A local attacker with low privileges can trigger kernel memory corruption, potentially leading to privilege escalation on affected devices. The issue is tracked under [CWE-787] (Out-of-bounds Write).

Critical Impact
Local attackers can corrupt kernel memory via unvalidated LUT input to the Exynos DPU driver, creating conditions for privilege escalation on affected Samsung mobile processors.

Affected Products

Samsung Exynos 1280, 1380, 1480, 1580, 1680
Samsung Exynos 2200, 2400, 2500, 2600
Devices running the Exynos DPU driver on the above processors

Discovery Timeline

2026-09-14 - CVE CVE-2026-23791 published to NVD
2026-09-14 - Last updated in NVD database

Technical Details for CVE-2026-23791

Vulnerability Analysis

The vulnerability resides in the Exynos DPU kernel driver, which handles display composition and color processing for Samsung mobile System-on-Chips (SoCs). The DPU exposes an interface that accepts color mode LUT data from user space. The driver processes this LUT input without validating the length of the supplied buffer against the destination structure in kernel memory.

Because the length check is missing, the driver writes attacker-controlled bytes past the intended kernel buffer boundary. This out-of-bounds write corrupts adjacent kernel memory. Depending on the layout, an attacker can influence kernel control structures or function pointers, escalating from a low-privileged local context toward higher kernel privileges.

The issue affects a broad set of Exynos parts spanning several generations of Samsung mobile processors. The scope change indicated in the CVSS vector reflects that a successful exploit crosses the boundary between the user process and the kernel security domain.

Root Cause

The root cause is missing input length validation in the color mode LUT parsing path within the Exynos DPU driver. The driver trusts a caller-supplied length or copies data without bounding it against the fixed-size kernel buffer, satisfying the conditions for [CWE-787].

Attack Vector

Exploitation requires local access with low privileges on the device. An attacker submits a crafted LUT payload to the DPU driver through its exposed interface, typically via an ioctl or equivalent kernel entry point. Attack complexity is high because reliable exploitation depends on kernel heap layout and timing. No user interaction is required.

A verified proof-of-concept is not publicly available. The vulnerability is described in prose in the Samsung CVE-2026-23791 Details advisory.

Detection Methods for CVE-2026-23791

Indicators of Compromise

Unexpected kernel panics, oops messages, or reboots referencing the Exynos DPU driver or color mode/LUT code paths.
Kernel address sanitizer (KASAN) reports of out-of-bounds writes in DPU functions on debug builds.
Unprivileged processes issuing repeated ioctl calls to DPU device nodes such as /dev/dpu* with oversized payloads.

Detection Strategies

Enable KASAN or equivalent kernel memory sanitizers in test builds to surface out-of-bounds writes in DPU LUT parsing.
Monitor mobile device management (MDM) telemetry for repeated abnormal terminations of processes interacting with the display stack.
Correlate crash dumps referencing Exynos DPU symbols with the installed Samsung security patch level.

Monitoring Recommendations

Track Samsung Mobile Security Bulletin patch levels across the device fleet and alert on devices missing the fix.
Ingest device crash reports and kernel logs into a centralized log platform for anomaly review.
Baseline normal usage of DPU ioctl interfaces and flag deviations by non-system UIDs.

How to Mitigate CVE-2026-23791

Immediate Actions Required

Apply the Samsung security update that addresses CVE-2026-23791 as soon as it is available for the affected Exynos-based device.
Inventory devices using Exynos 1280, 1380, 1480, 1580, 1680, 2200, 2400, 2500, and 2600 processors and prioritize patch rollout.
Restrict installation of untrusted applications, since exploitation requires local code execution on the device.

Patch Information

Samsung publishes fixes through its semiconductor product security update process. Refer to the Samsung Product Security Updates portal and the specific Samsung CVE-2026-23791 Details advisory for the fixed driver versions and integration guidance for device manufacturers.

Workarounds

Enforce application allowlisting through MDM to reduce the population of local code capable of reaching the DPU driver.
Disable sideloading and developer options on managed devices to limit exposure to malicious local applications.
Where supported by the platform, restrict access to DPU device nodes to system components only.

bash

# Verify Samsung security patch level on an Android device via ADB
adb shell getprop ro.build.version.security_patch
adb shell getprop ro.product.board