CVE-2026-21033: Samsung Assistant ExpressHomeWidgetReceiver Improper Component Export Vulnerability

Technical summary

The vulnerability stems from improper export of Android application components within Samsung Assistant's ExpressHomeWidgetReceiver prior to version 9.3.14. In Android's component model, broadcast receivers and other components can be exported, making them callable by other applications on the same device. When components are exported without proper permission enforcement, a local application can invoke them to perform unintended actions. This flaw allows an unprivileged local process to execute arbitrary scripts through the exposed receiver, bypassing normal sandboxing boundaries. The attack surface is limited to the device itself (no network propagation), but the impact is significant for affected systems.

Business impact

Exploitation could lead to unauthorized script execution within the Samsung Assistant context, potentially enabling a compromised or malicious application to perform actions such as data exfiltration, privilege escalation, or lateral movement within the device's application environment. For organizations deploying Samsung devices with Assistant enabled, this represents a moderate but concrete risk that could compromise device integrity and user data confidentiality. The requirement for local access limits exposure to scenarios where devices are shared, publicly accessible, or where users sideload untrusted applications.

Affected systems

Samsung Assistant versions prior to 9.3.14 are affected. Organizations should inventory Samsung devices running this product and determine which firmware and application versions are currently deployed. Samsung Assistant is commonly bundled with Samsung devices and may be auto-updated through Samsung's systems, but verification against your device inventory is essential.

Exploitability

This vulnerability has not been added to the CISA Known Exploited Vulnerabilities (KEV) catalog as of the information provided. However, the attack vector is local and the complexity is low, meaning an attacker on or with code running on the same device can exploit it without complex setup or user interaction. The barrier to exploitation is primarily gaining local code execution first—a common stepping stone in multi-stage attacks or in environments where users install untrusted applications.

Remediation

Update Samsung Assistant to version 9.3.14 or later. Samsung should have published security patches addressing the component export issue. Verify patched versions through Samsung's official security bulletins and device management channels. Additionally, restrict installation of untrusted applications on devices running older Assistant versions to reduce the local attack surface.

Patch guidance

Obtain and deploy Samsung Assistant version 9.3.14 or later through official Samsung channels, such as the Galaxy Store or automatic system updates. Verify patch status by checking the installed version within Samsung Assistant settings or through your mobile device management (MDM) platform if one is in use. Test patches in a non-production environment before broader rollout to ensure compatibility with existing workflows.

Detection guidance

Monitor for unexpected invocations of ExpressHomeWidgetReceiver from non-standard application processes using Android security logs or enterprise mobile threat defense solutions. Inspect application permissions and component exports on affected devices for signs of tampering. If possible, enable enhanced logging within Samsung Assistant or use MDM telemetry to track version deployment and identify unpatched devices in your environment.

Why prioritize this

With a CVSS 3.1 score of 7.1 (HIGH severity), this vulnerability merits prompt attention. The combination of low attack complexity, no user interaction required, and high impact on confidentiality and integrity makes it a meaningful risk. While local-only exploitation limits immediate threat scope, the prevalence of Samsung devices and the ease of local code execution in certain scenarios justify prioritizing patch deployment.

Risk score, explained

The CVSS 3.1 vector (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N) yields a score of 7.1. The attack vector is local (AV:L), reflecting that an attacker must already have some presence on the device. Attack complexity is low (AC:L), meaning no special setup or timing is needed once an attacker has a foothold. Privilege requirement is low (PR:L), so a standard unprivileged user can trigger the flaw. No user interaction (UI:N) is required. The impact is confined to the affected component and user context (S:U), with high confidentiality and integrity impact (C:H/I:H) but no availability impact (A:N). The absence of ransomware or active exploitation data tempers urgency slightly but does not reduce the inherent severity.

Frequently asked questions