CVE-2026-21103 in Samsung
Summary
by MITRE • 09/09/2026
Path traversal in GalaxyDiagnostics prior to SMR Sep-2026 Release 1 allows physical attackers to access files with system privilege.
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Analysis
by VulDB Data Team • 09/09/2026
The vulnerability identified as a path traversal flaw within the GalaxyDiagnostics software, specifically affecting versions prior to the September 2026 Release 1 update, represents a critical security deficiency that compromises the integrity of file system access controls. This issue stems from an insufficient validation mechanism when processing user-supplied input or internal diagnostic requests. The application fails to properly sanitize directory traversal sequences, such as dot-dot-slash characters, which allows an attacker to manipulate file paths beyond their intended scope. By exploiting this lack of boundary enforcement, the software inadvertently grants access to files and directories that are normally restricted by operating system permissions, effectively bypassing standard security boundaries designed to isolate application data from sensitive system resources.
From a technical perspective, this flaw aligns with Common Weakness Enumeration category CWE-22: Improper Limitation of a Pathname to a Restricted Directory. The root cause lies in the failure to canonicalize or strictly validate file paths before performing read or write operations. When an attacker constructs a malicious request containing relative path traversal sequences, the underlying system resolves these paths incorrectly, leading to access outside the designated sandboxed directory. This behavior is particularly dangerous because it does not require network exposure; instead, it relies on physical proximity and local interaction with the device running GalaxyDiagnostics. The vulnerability exploits the trust relationship between the application logic and the operating system's file handling routines, allowing low-privilege processes to escalate their access rights by reading sensitive configuration files, logs, or other critical data stored in protected directories.
The operational impact of this path traversal vulnerability is severe for physical attackers who have gained local access to the device. Once an attacker can read arbitrary files with system privileges, they may extract credentials, encryption keys, session tokens, or proprietary diagnostic algorithms embedded within configuration files. This information disclosure facilitates further attacks, including privilege escalation and lateral movement across a network if the extracted data contains sensitive authentication material. Furthermore, depending on the specific implementation details of GalaxyDiagnostics, there is potential for write-based exploitation where an attacker could overwrite critical system files, leading to denial of service or remote code execution scenarios. The ability to access files with elevated privileges undermines the principle of least privilege and compromises the confidentiality and integrity of the entire diagnostic infrastructure.
To mitigate this vulnerability, organizations must prioritize applying the official patch included in GalaxyDiagnostics Release 1 scheduled for September 2026. Until that update is available, administrators should implement strict physical security controls to prevent unauthorized individuals from accessing the device's local interfaces or console ports. Additionally, deploying host-based intrusion detection systems can help monitor for anomalous file access patterns indicative of path traversal attempts. It is also advisable to review application configurations to ensure that any exposed diagnostic endpoints are restricted to trusted internal networks and require strong authentication mechanisms where applicable. Regular security audits focusing on input validation and path handling logic will further reduce the risk of similar flaws in future software versions, ensuring robust defense against local privilege escalation attacks as categorized under MITRE ATT&CK techniques related to Local File Access and Data from Information Repositories.