CVE-2026-58941: IOMMU Privilege Escalation Vulnerability

CVE-2026-58941 Overview

CVE-2026-58941 is an out-of-bounds read/write vulnerability in the Android kernel's iommu.c component. The flaw stems from improper input validation across multiple functions in the Input/Output Memory Management Unit (IOMMU) code. A local attacker with low privileges can trigger the condition to achieve local escalation of privilege. Exploitation requires no user interaction and no additional execution privileges. The issue is tracked under CWE-20: Improper Input Validation and was addressed in the Android Security Bulletin September 2026.

Critical Impact
A local attacker can escalate privileges to kernel context without user interaction, gaining full control over the affected Android device.

Affected Products

Android Open Source Project (AOSP) kernel — iommu.c component
Android devices receiving patches from the September 2026 Security Bulletin
Downstream Android distributions incorporating the affected kernel common branch

Discovery Timeline

2026-09-08 - CVE-2026-58941 published to the National Vulnerability Database
2026-09-08 - Last updated in NVD database
September 2026 - Fix referenced in the Android Security Bulletin

Technical Details for CVE-2026-58941

Vulnerability Analysis

The vulnerability resides in multiple functions within iommu.c, the source file that implements Android's IOMMU subsystem. IOMMU code translates device-visible virtual addresses into physical addresses and enforces DMA boundaries. Improper validation of input parameters allows accesses to fall outside the intended memory region. Both read and write primitives are exposed, giving an attacker flexibility in shaping an exploit. Successful exploitation grants kernel-level control from an unprivileged local context.

Root Cause

The root cause is improper input validation [CWE-20]. Untrusted inputs reach memory access routines in iommu.c without adequate bounds checking. Sizes, offsets, or indices supplied through the interface are used to compute pointers or array positions that exceed allocated buffers. The upstream fix is captured in the Android Kernel Commit Update and the Android Kernel Commit Patch, which introduce validation before affected memory operations.

Attack Vector

The attack vector is local. A malicious application or process running on the device invokes the vulnerable IOMMU code paths through normal kernel interfaces. Because no user interaction is required, exploitation can be chained after initial device compromise from an app installed by other means. The attacker uses the out-of-bounds primitives to corrupt kernel data structures and pivot to arbitrary code execution in kernel mode. See the Android Security Bulletin September 2026 for the vendor's classification.

No verified public proof-of-concept code is available at this time. Refer to the linked kernel commits for the exact functions and validation logic changed.

Detection Methods for CVE-2026-58941

Indicators of Compromise

Unexpected kernel oops or panic messages referencing iommu functions in dmesg or logcat kernel buffers
Applications performing repeated or malformed ioctl calls against IOMMU-related device nodes
New processes running with elevated (root or system) privileges without a legitimate provisioning path

Detection Strategies

Monitor kernel logs for out-of-bounds access reports, KASAN (Kernel Address Sanitizer) alerts, or stack traces originating in iommu.c
Inspect installed applications for native components that interact directly with kernel IOMMU interfaces outside vendor use cases
Correlate crash telemetry from Android devices in a fleet to identify clustered failures tied to the IOMMU subsystem

Monitoring Recommendations

Ingest Android device logs and crash reports into a centralized analytics pipeline for behavioral review
Track patch level (ro.build.version.security_patch) across the fleet and alert on devices missing the September 2026 patch level
Baseline normal IOMMU-related syscall patterns and flag deviations, particularly from newly installed applications

How to Mitigate CVE-2026-58941

Immediate Actions Required

Apply the September 2026 Android security patch level to all managed devices as soon as the OEM release is available
Restrict installation of applications from untrusted sources through Mobile Device Management (MDM) policies
Inventory devices that cannot receive the patch and plan for retirement or network isolation

Patch Information

The fix is delivered through the Android common kernel via two commits: 6bc773e9c9f8ec6c5c431934462badbbb7d21767 and ba7833622fc3581c388d0da922aaab529aec43b3. Devices must be updated to a security patch level of 2026-09-01 or later, as documented in the Android Security Bulletin September 2026. Contact the device Original Equipment Manufacturer (OEM) if updates are not yet published.

Workarounds

No vendor-supplied workaround exists; patching is the only supported remediation
Reduce risk by limiting sideloaded applications and enforcing Google Play Protect on managed devices
Enforce least-privilege application permissions and disable developer options on production devices

bash

# Verify Android security patch level on a device
adb shell getprop ro.build.version.security_patch
# Expected value for remediation: 2026-09-01 or later