CVE-2026-20986: Samsung Members Path Traversal Flaw

CVE-2026-20986 Overview

A path traversal vulnerability has been identified in Samsung Members application prior to Chinese version 15.5.05.4. This vulnerability allows local attackers to exploit improper input validation to overwrite data within the Samsung Members application. Path traversal flaws occur when an application fails to properly sanitize user-supplied file paths, enabling attackers to access or modify files outside of the intended directory structure.

Critical Impact

Local attackers can leverage this path traversal vulnerability to overwrite arbitrary data within the Samsung Members application, potentially leading to data corruption, configuration tampering, or denial of service conditions on affected Samsung devices.

Affected Products

• Samsung Members (Chinese version) prior to version 15.5.05.4
• Samsung mobile devices running vulnerable Samsung Members application versions

Discovery Timeline

• 2026-02-04 - CVE CVE-2026-20986 published to NVD
• 2026-02-04 - Last updated in NVD database

Technical Details for CVE-2026-20986

Vulnerability Analysis

This path traversal vulnerability exists in the Samsung Members application and can be exploited by local attackers who have access to the device. The vulnerability stems from insufficient validation of file path inputs, which allows an attacker to craft malicious path strings containing directory traversal sequences (such as ../) to escape the intended directory context.

When successfully exploited, an attacker can overwrite files within the Samsung Members application's data storage area. While the attack requires local access to the device, it does not require any special privileges or user interaction to execute. The impact is primarily focused on data integrity and availability, as attackers can corrupt or overwrite application data.

Root Cause

The root cause of this vulnerability is improper input validation in the Samsung Members application's file handling routines. The application fails to adequately sanitize or validate file path inputs before using them in file system operations. This allows attackers to include path traversal sequences that navigate outside the intended directory boundaries.

Specifically, the application does not properly:

• Canonicalize file paths before use
• Reject or sanitize directory traversal sequences (../, ..\)
• Implement proper allowlist-based path validation

Attack Vector

The attack vector is local, meaning an attacker must have access to the device to exploit this vulnerability. The attack can be executed without requiring elevated privileges or user interaction. A local attacker could exploit this flaw by:

1. Crafting a malicious file path containing directory traversal sequences
2. Submitting this path through a vulnerable input mechanism in the Samsung Members application
3. Causing the application to write data to an unintended location within its accessible file system scope

The vulnerability allows modification of application data but does not enable arbitrary file system access outside of the Samsung Members application's context, limiting the overall impact to integrity and availability concerns within the application scope.

Detection Methods for CVE-2026-20986

Indicators of Compromise

• Unexpected modifications to Samsung Members application data files
• Anomalous file write operations targeting Samsung Members application directories
• Application crashes or unexpected behavior in Samsung Members indicating data corruption
• Log entries showing unusual file path access patterns with traversal sequences

Detection Strategies

• Monitor Samsung Members application logs for file operations containing ../ or similar traversal patterns
• Implement file integrity monitoring on Samsung Members application data directories
• Review application crash reports for signs of data corruption or unexpected file access
• Use mobile device management (MDM) solutions to detect anomalous application behavior

Monitoring Recommendations

• Enable verbose logging for Samsung Members application where available
• Configure alerts for unexpected file modifications in application data directories
• Regularly audit installed application versions across managed device fleets
• Monitor for Samsung security bulletins and update notifications

How to Mitigate CVE-2026-20986

Immediate Actions Required

• Update Samsung Members application to Chinese version 15.5.05.4 or later immediately
• Review Samsung Members application data for signs of tampering or corruption
• Ensure automatic application updates are enabled on Samsung devices
• Consider temporarily restricting device access if updates cannot be immediately applied

Patch Information

Samsung has released a security update addressing this vulnerability. Users should update the Samsung Members application to version 15.5.05.4 or later for the Chinese version. The patch information is available in the Samsung Mobile Security Update bulletin for February 2026.

To update the application:

1. Open the Galaxy Store or Google Play Store on your Samsung device
2. Search for "Samsung Members"
3. Check if an update is available and install it
4. Verify the installed version is 15.5.05.4 or higher

Workarounds

• Limit physical access to affected devices until the patch can be applied
• Enable device encryption to protect data at rest
• Use mobile device management (MDM) to enforce application version requirements
• Regularly backup Samsung Members data to enable recovery from potential data corruption