CVE-2026-21025: Samsung Android Privilege Escalation Flaw

CVE-2026-21025 Overview

CVE-2026-21025 is an incorrect privilege assignment vulnerability in the Telephony component of Samsung Android. The flaw exists in builds prior to the Samsung Mobile Release (SMR) June 2026 Release 1 and affects Samsung Android 14, 15, and 16. A local attacker with code execution on the device can leverage the misassigned privileges to access sensitive information exposed by the Telephony service. Exploitation does not require user interaction or elevated privileges, but the attacker must already have local access to the device. Samsung addressed the issue in its June 2026 monthly security maintenance release.

Critical Impact
Local applications without legitimate telephony permissions can read sensitive telephony-related information, bypassing the Android permission model on unpatched Samsung devices.

Affected Products

Samsung Android 14.0 (SMR releases prior to Jun-2026 R1)
Samsung Android 15.0 (SMR releases prior to Jun-2026 R1)
Samsung Android 16.0 (SMR releases prior to Jun-2026 R1)

Discovery Timeline

2026-06-05 - CVE-2026-21025 published to NVD
2026-06-06 - Last updated in NVD database
June 2026 - Samsung releases SMR Jun-2026 Release 1 addressing the vulnerability via the Samsung Mobile Security Update

Technical Details for CVE-2026-21025

Vulnerability Analysis

The vulnerability resides in the Telephony component, a privileged Android system service that manages cellular, SIM, and carrier-related data. Samsung's implementation assigns incorrect privileges to one or more Telephony interfaces, allowing callers that should not possess telephony-related permissions to invoke protected functionality. The defect is categorized under [NVD-CWE-Other] because it does not map cleanly to a single CWE, but it is consistent with broken access control on an exported component. Attackers can obtain data normally gated by permissions such as READ_PHONE_STATE or carrier-privileged APIs.

Root Cause

The root cause is improper privilege assignment within the Telephony service's permission checks or manifest-level protection levels. Either an exported interface lacks an appropriate signature or privileged protection level, or a runtime permission check is skipped on a code path that returns sensitive data. The result is that unprivileged local code is treated as if it held telephony privileges.

Attack Vector

Exploitation requires local access. A malicious or compromised application installed on the device queries the affected Telephony interface and receives sensitive information that the Android permission model should have blocked. No user interaction is required, and the attacker does not need prior privileges beyond the ability to run code on the device. The exposed data may include identifiers and state information useful for device fingerprinting, tracking, or follow-on attacks. The vulnerability does not allow remote exploitation across the network.

No public proof-of-concept code is available, and the issue is not listed in the CISA Known Exploited Vulnerabilities catalog. The EPSS estimate places near-term exploitation likelihood very low.

Detection Methods for CVE-2026-21025

Indicators of Compromise

Installed applications that query telephony APIs without declaring corresponding permissions in their manifest.
Unexpected access to SIM, carrier, or subscriber identifiers by third-party applications running on Samsung Android 14, 15, or 16.
Devices whose build fingerprint reflects an SMR level earlier than Jun-2026 R1 despite being eligible for the June 2026 update.

Detection Strategies

Inventory Samsung Android endpoints with mobile device management (MDM) tooling and flag devices reporting a security patch level earlier than June 1, 2026.
Use mobile application vetting to identify apps invoking Telephony Manager interfaces without holding the matching declared permissions.
Review app behavior in enterprise app stores for repeated reads of telephony state by applications outside the dialer, messaging, or carrier-service categories.

Monitoring Recommendations

Forward MDM compliance and patch-level telemetry to a central logging platform and alert on Samsung devices stuck below SMR Jun-2026 R1.
Monitor enterprise app install events for newly sideloaded packages on Samsung devices and correlate with telephony API usage.
Track Samsung's monthly security bulletins so future Telephony fixes are mapped into vulnerability management workflows.

How to Mitigate CVE-2026-21025

Immediate Actions Required

Deploy the Samsung SMR Jun-2026 Release 1 update to all managed Samsung Android 14, 15, and 16 devices through MDM or carrier OTA channels.
Identify devices that have not received the June 2026 patch level and prioritize them for remediation or quarantine from sensitive workloads.
Restrict sideloading and enforce installation only from vetted enterprise or official app stores until devices are patched.

Patch Information

Samsung addressed CVE-2026-21025 in the SMR Jun-2026 Release 1 security maintenance release. Patch details and the list of fixed CVEs are published in the Samsung Mobile Security Update for June 2026. Devices report the applied SMR level under Settings > About phone > Software information as the Android security patch level.

Workarounds

Limit installation of untrusted third-party applications on affected devices until the SMR Jun-2026 R1 update is applied.
Apply MDM policies that block unknown sources and require attestation of the device security patch level before granting access to corporate resources.
Where patching is delayed, segregate affected devices from access to sensitive business applications that rely on the device's telephony identifiers for trust decisions.