CVE-2026-21062 Overview
CVE-2026-21062 is an authorization bypass vulnerability in Samsung's SemClipboardService component on affected Galaxy devices. The flaw allows local attackers to access clipboard data without holding the required permissions. Samsung addressed the issue in the Samsung Mobile Release (SMR) Aug-2026 Release 1 security update.
The weakness is classified under [CWE-939: Improper Authorization in Handler for Custom URL Scheme], reflecting insufficient caller validation in the clipboard service. Because the clipboard often contains passwords, one-time codes, and other transient secrets, unauthorized read access poses a meaningful data exposure risk on multi-app Android devices.
Critical Impact
A local application without clipboard permissions can read clipboard contents handled by SemClipboardService, potentially exposing credentials, authentication codes, and other sensitive user data.
Affected Products
- Samsung Galaxy devices running Samsung firmware prior to SMR Aug-2026 Release 1
- Samsung SemClipboardService system component
- Devices dependent on Samsung's monthly Security Maintenance Release (SMR) update cycle
Discovery Timeline
- 2026-08-10 - CVE-2026-21062 published to NVD alongside the Samsung Security Update August 2026
- 2026-08-10 - Last updated in NVD database
Technical Details for CVE-2026-21062
Vulnerability Analysis
The issue resides in SemClipboardService, a Samsung-specific extension of the Android clipboard framework that manages clipboard content across system and third-party applications. The service exposes interfaces that should enforce authorization checks before returning clipboard data. Prior to SMR Aug-2026 Release 1, one or more of these interfaces fail to correctly validate whether the calling application is entitled to read the clipboard.
A local attacker with the ability to run an unprivileged application on the device can invoke the affected interface and retrieve clipboard content bypassing intended access controls. The vulnerability requires local access and low privileges, and does not require user interaction. Impact is limited to confidentiality of clipboard data; integrity and availability are not affected.
Root Cause
The root cause is missing or incomplete authorization enforcement inside SemClipboardService handlers. Under [CWE-939], the service accepts requests without verifying that the caller holds the appropriate permission or foreground state required by Android's clipboard access model. This gap effectively downgrades a permission-gated operation to an operation any local app can perform.
Attack Vector
Exploitation is local. A malicious or compromised application installed on the device binds to the vulnerable service interface and issues clipboard read requests. Because the check is absent or flawed, the service returns clipboard data to the caller. No verified proof-of-concept has been published, and there is no evidence of exploitation in the wild. See the Samsung Security Update August 2026 bulletin for the vendor's advisory.
No verified exploit code is available. The vulnerability is described in prose only, consistent with Samsung's disclosure practice for SMR entries.
Detection Methods for CVE-2026-21062
Indicators of Compromise
- Unexpected applications binding to Samsung clipboard service interfaces or invoking SemClipboardManager APIs without a corresponding user paste action.
- Foreground/background transitions where a non-focused app issues clipboard read calls shortly after a sensitive app (password manager, banking, authenticator) copies data.
- Newly installed or side-loaded APKs on managed devices that request clipboard-adjacent interactions outside expected functionality.
Detection Strategies
- Enroll Samsung devices in a Mobile Threat Defense or MDM solution and monitor for applications invoking clipboard-related system services.
- Review Android system logs and Samsung Knox audit events for anomalous access to SemClipboardService from non-system UIDs.
- Correlate clipboard access telemetry with app install events to identify apps that read clipboard data without a user-facing paste operation.
Monitoring Recommendations
- Track SMR patch level (ro.build.version.security_patch) across the mobile fleet and alert on devices below Aug-2026 Release 1.
- Monitor app inventory changes and flag installations from unknown sources on devices holding sensitive corporate data.
- Alert on password manager and authenticator apps running alongside untrusted third-party apps on unpatched devices.
How to Mitigate CVE-2026-21062
Immediate Actions Required
- Install the Samsung SMR Aug-2026 Release 1 update on all affected Galaxy devices as soon as the vendor delivers it to your device model and carrier.
- Enforce a minimum Android security patch level policy through MDM to block or quarantine devices that have not received the August 2026 SMR.
- Restrict installation of applications from unknown sources on corporate-managed Samsung devices.
Patch Information
Samsung fixed CVE-2026-21062 in the SMR Aug-2026 Release 1 firmware update. The vendor bulletin is available at Samsung Mobile Security Updates - August 2026. Deploy the update through the device's Software Update mechanism or through your enterprise mobility management platform.
Workarounds
- Advise users of unpatched devices to avoid copying passwords, MFA codes, or other secrets to the clipboard; use password manager autofill instead.
- Limit installation of untrusted third-party applications on unpatched devices until the SMR Aug-2026 Release 1 update is applied.
- Use enterprise containerization (Samsung Knox workspace) to isolate corporate data and clipboard operations from personal apps.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
