CVE-2025-66002 in smb4k
Summary
by MITRE • 01/08/2026
An Improper Neutralization of Argument Delimiters in a Command ('Argument Injection') vulnerability allows local users ton perform arbitrary unmounts via smb4k mount helper
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Analysis
by VulDB Data Team • 01/09/2026
This vulnerability represents a critical argument injection flaw that affects the smb4k mount helper utility, creating a significant security risk for local users within networked file system environments. The issue stems from inadequate input sanitization mechanisms that fail to properly neutralize argument delimiters in command execution contexts, allowing malicious actors to inject arbitrary commands through carefully crafted mount parameters. The vulnerability specifically impacts systems where smb4k serves as an intermediary for mounting smb/cifs shares, creating a potential attack vector that could be exploited to execute unauthorized operations on the target system. According to the CWE taxonomy, this corresponds to CWE-77, which describes improper neutralization of special elements used in command execution contexts, making it a direct descendant of command injection vulnerabilities that have been extensively documented in security literature.
The technical exploitation of this vulnerability occurs when local users manipulate the argument delimiters within smb4k's command execution flow, enabling them to inject additional commands that bypass normal access controls and execute with the privileges of the mount helper process. This flaw particularly affects systems running smb4k as a mount helper component where command line arguments are directly passed to system execution functions without proper sanitization. The operational impact extends beyond simple command execution to include potential unauthorized system modifications, data exfiltration, and privilege escalation opportunities. Attackers could leverage this vulnerability to perform arbitrary unmount operations, potentially disrupting legitimate network services and creating denial of service conditions while simultaneously gaining unauthorized access to system resources. The vulnerability's persistence in local execution contexts means that any user with access to the mount helper functionality could exploit this weakness without requiring elevated privileges beyond standard user access.
The security implications of CVE-2025-66002 extend into multiple domains of the attack lifecycle as defined by the MITRE ATT&CK framework, particularly mapping to techniques involving command and scripting interpreter execution, privilege escalation, and defense evasion. The vulnerability's impact aligns with ATT&CK tactic TA0002 (Execution) and TA0004 (Privilege Escalation) through the unauthorized command execution capabilities it provides. Organizations utilizing smb4k for network file system management face heightened risk of unauthorized system compromise, as this vulnerability can be exploited without requiring network access or sophisticated attack infrastructure. The attack surface is particularly concerning in enterprise environments where smb4k may be used for automated mounting operations, as these scenarios often involve elevated privileges and persistent access to critical network resources. System administrators should consider implementing comprehensive monitoring for suspicious mount operations and command execution patterns that could indicate exploitation attempts.
Mitigation strategies for this vulnerability should focus on immediate input validation and sanitization of all command arguments within the smb4k mount helper functionality. Organizations should implement strict parameter validation that prevents delimiter injection and ensure that all user-supplied arguments are properly escaped or quoted before being passed to system execution functions. The recommended approach includes deploying updated versions of smb4k that address the argument injection flaw, implementing privilege separation for mount helper processes, and establishing comprehensive logging of mount operations to detect anomalous behavior. Additionally, security teams should consider implementing network segmentation to limit access to systems running smb4k, particularly in environments where local privilege escalation could have significant impact. Regular security assessments should be conducted to identify similar vulnerabilities in other mount helper utilities and system components that may be susceptible to command injection attacks, as this represents a common pattern in system administration tools that handle user input in execution contexts.