CVE-2026-20977: Samsung Android Auth Bypass Vulnerability

CVE-2026-20977 Overview

CVE-2026-20977 is an improper access control vulnerability in the Samsung Emergency Sharing feature on Samsung Android devices. The flaw lets a local attacker interrupt the functioning of the Emergency Sharing component, affecting availability of the service. Samsung addressed the issue in the SMR Feb-2026 Release 1 security maintenance update.

The vulnerability impacts Samsung devices running Android 14, 15, and 16 prior to the February 2026 patch. Exploitation requires local access to the device but does not require privileges or user interaction. The weakness is tracked under [NVD-CWE-noinfo] and falls into the Improper Access Control category.

Critical Impact

A local attacker on an affected Samsung Android device can disrupt the Emergency Sharing feature, potentially preventing users from sharing emergency information when needed.

Affected Products

• Samsung Android 14 prior to SMR Feb-2026 Release 1
• Samsung Android 15 prior to SMR Feb-2026 Release 1
• Samsung Android 16 prior to SMR Feb-2026 Release 1

Discovery Timeline

• 2026-02-04 - CVE CVE-2026-20977 published to NVD
• 2026-02-05 - Last updated in NVD database

Technical Details for CVE-2026-20977

Vulnerability Analysis

The vulnerability resides in the Emergency Sharing component shipped with Samsung's Android distribution. Emergency Sharing allows users to broadcast their location and status to designated contacts during emergencies. Improper access control in this component means that access decisions are not enforced correctly for one or more of its interfaces.

A local attacker, such as a malicious application installed on the device, can interact with the affected component without holding the privileges that should be required. The result is interruption of Emergency Sharing functionality, classified as an availability impact on the vulnerable component.

The issue is local in scope and does not provide a path to remote compromise or data exfiltration. However, disruption of emergency-related features carries safety implications for end users who rely on them.

Root Cause

The root cause is missing or inadequate access control checks on entry points exposed by the Emergency Sharing component. Samsung's advisory categorizes the flaw as improper access control and the NVD record provides no further sub-classification beyond NVD-CWE-noinfo. The fix is delivered as part of the February 2026 Samsung Mobile Security Update.

Attack Vector

Exploitation requires local access to the device. An attacker delivers a malicious app or runs code in a local context that invokes the affected interface exposed by Emergency Sharing. Because no privileges or user interaction are required, any app permitted to run on the device can trigger the disruption. The attack does not cross trust boundaries beyond the affected component.

No public proof-of-concept code, exploit module, or in-the-wild exploitation has been documented for CVE-2026-20977. Refer to the Samsung Security Update February 2026 advisory for vendor technical details.

Detection Methods for CVE-2026-20977

Indicators of Compromise

• Unexpected crashes, restarts, or unresponsiveness of the Samsung Emergency Sharing service or its UI on affected devices.
• Installation of untrusted third-party applications that request access to emergency-related system interfaces.
• Device build numbers reflecting Samsung Android 14, 15, or 16 builds prior to the SMR Feb-2026 Release 1 patch level.

Detection Strategies

• Inventory managed Samsung devices and flag any whose security patch level predates February 2026.
• Review installed application telemetry from mobile device management (MDM) systems for unsanctioned apps invoking emergency or location-sharing system interfaces.
• Monitor Android logcat and crash reports for repeated failures referencing Emergency Sharing components.

Monitoring Recommendations

• Configure MDM compliance policies to alert when the Samsung security patch level falls below February 2026.
• Track Samsung's monthly Security Maintenance Release (SMR) bulletins to maintain coverage across the Samsung Android fleet.
• Audit user reports of Emergency Sharing failures and correlate them with device patch levels and recently installed applications.

How to Mitigate CVE-2026-20977

Immediate Actions Required

• Apply the Samsung SMR Feb-2026 Release 1 update on all supported Samsung Android 14, 15, and 16 devices.
• Enforce minimum patch-level compliance through your MDM solution and block non-compliant devices from accessing sensitive corporate resources.
• Restrict installation of applications from untrusted sources and review permissions granted to existing apps.

Patch Information

Samsung released a fix as part of the February 2026 Security Maintenance Release. Users and administrators should install the SMR Feb-2026 Release 1 update or any subsequent monthly update. Full details and the list of addressed CVEs are published in the Samsung Security Update February 2026 bulletin.

Workarounds

• No vendor-supplied workaround is documented. Applying the February 2026 SMR is the supported remediation.
• Limit physical and local access to devices that cannot yet be updated, and avoid installing applications from outside Galaxy Store or Google Play.
• Where feasible, defer reliance on Emergency Sharing on unpatched devices until the SMR Feb-2026 Release 1 update is applied.