CVE-2026-21028: Samsung Android Information Disclosure Flaw

CVE-2026-21028 Overview

CVE-2026-21028 is an improper access control vulnerability in the AuditLogService component of Samsung Android. The flaw exists in versions prior to the Samsung Mobile Release (SMR) June 2026 Release 1. Local attackers with code execution on the device can query the service to retrieve sensitive information that should be restricted to privileged callers.

Samsung published the issue in its June 2026 security maintenance release. The vulnerability requires local access and no user interaction, but does not grant code execution or integrity impact on its own.

Critical Impact
Local applications or processes can read sensitive audit log data from AuditLogService without proper authorization, exposing information that may aid further attacks.

Affected Products

Samsung Android 16.0 (base release without SMR patch)
Samsung Android 16.0 with SMR releases from August 2025 through May 2026
Samsung Android devices not yet updated to SMR Jun-2026 Release 1

Discovery Timeline

2026-06-05 - CVE-2026-21028 published to NVD
2026-06-06 - Last updated in NVD database

Technical Details for CVE-2026-21028

Vulnerability Analysis

The vulnerability resides in AuditLogService, a Samsung-specific Android system service responsible for recording and exposing audit log entries. The service fails to enforce adequate access control checks on callers requesting log data. As a result, an unprivileged local process can invoke service interfaces and receive audit records intended for privileged components only.

NVD classifies the weakness under NVD-CWE-noinfo because Samsung's advisory does not disclose specific CWE details. Based on the description, the issue maps to Improper Access Control. The exposure is limited to information disclosure with no direct integrity or availability impact.

Root Cause

The root cause is a missing or insufficient permission check inside AuditLogService. Android services typically gate sensitive Binder interfaces with checkCallingPermission() calls or signature-level permissions. In the affected builds, callers can reach data paths that should have required elevated privileges, exposing audit content to any local app or shell user.

Attack Vector

An attacker must already have local access, such as an installed application or an ADB shell session on the device. The attacker invokes the exposed AuditLogService interface through the Android Binder IPC mechanism. No user interaction and no additional privileges are required. The disclosed audit records may include device identifiers, security event metadata, or other information useful for reconnaissance and follow-on attacks.

Samsung has not published technical exploitation details. See the Samsung Security Update June 2026 for vendor-supplied information.

Detection Methods for CVE-2026-21028

Indicators of Compromise

Unexpected applications binding to or querying the AuditLogService Binder interface
Anomalous read access patterns against system audit log endpoints from non-system UIDs
Installed applications requesting or invoking system services outside their declared functionality

Detection Strategies

Inventory Samsung Android devices and compare installed SMR patch level against SMR Jun-2026 Release 1 or later
Review mobile threat defense telemetry for processes interacting with privileged system services
Audit sideloaded applications and recently installed APKs on managed Samsung devices for suspicious permission usage

Monitoring Recommendations

Enforce mobile device management (MDM) compliance policies that flag devices missing the June 2026 SMR patch
Collect Android logcat and security event data into a centralized data lake for retrospective analysis
Alert on applications that attempt to access system audit functionality outside expected workflows

How to Mitigate CVE-2026-21028

Immediate Actions Required

Apply Samsung SMR Jun-2026 Release 1 or later to all affected Samsung Android 16.0 devices
Use MDM policies to enforce minimum patch level and quarantine devices below the required SMR release
Restrict installation of untrusted applications on devices that cannot be patched immediately

Patch Information

Samsung addressed the issue in the June 2026 Samsung Mobile Release. Devices must be updated to SMR Jun-2026 Release 1 or any subsequent SMR. Patch availability depends on device model and carrier. Refer to the Samsung Security Update June 2026 advisory for the full list of fixed components and affected models.

Workarounds

No official workaround is published by Samsung; patching is the only supported remediation
Limit physical and ADB access to unpatched devices to reduce local attack surface
Avoid installing applications from unverified sources until the SMR update is applied

bash

# Verify Samsung Android security patch level via ADB
adb shell getprop ro.build.version.security_patch
adb shell getprop ro.build.version.release
# Confirm value reflects June 2026 SMR or later before returning device to service