CVE-2026-62325 in goshs
Summary
by MITRE • 07/29/2026
goshs is a feature-rich single-binary file server for red teamers and developers. From 2.1.3 until 2.1.4, the sftpserver/sftpserver.go password handler used Username != "" && Password != "", so running goshs with -b 'admin:' -sftp and no -fkf left both SFTP authentication handlers unset and allowed unauthenticated file access. This issue is fixed in version 2.1.4.
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Analysis
by VulDB Data Team • 07/29/2026
The goshs tool represents a sophisticated single-binary file server designed for both red team operations and developer environments, offering comprehensive functionality including HTTP and SFTP server capabilities. This particular vulnerability emerged within the sftpserver component between versions 2.1.3 and 2.1.4, specifically affecting the password authentication handler implementation. The flaw manifested in the sftpserver.go file where the authentication logic evaluated Username = "" conditions, creating a critical security gap when certain command-line parameters were utilized.
When operators executed goshs with the specific flags -b 'admin:' -sftp and omitted the -fkf parameter, the system failed to properly configure both SFTP authentication handlers. This configuration oversight created an authentication bypass scenario where the absence of proper credential validation allowed any client to establish SFTP connections without providing valid credentials. The vulnerability directly exploited a logical flaw in the conditional authentication checks, enabling unauthenticated access to file transfer operations through the SFTP interface.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it fundamentally undermines the security posture of systems running vulnerable versions of goshs. Attackers could leverage this weakness to perform unauthorized file transfers, potentially exfiltrating sensitive data or establishing persistent access points within target environments. This issue particularly affects red team operations where maintaining operational security and avoiding detection is paramount, as the vulnerability creates an unintended backdoor that bypasses normal authentication mechanisms.
The technical root cause aligns with CWE-287, which addresses improper authentication issues in software systems, specifically targeting the scenario where authentication checks are insufficient or improperly configured. This vulnerability also maps to ATT&CK technique T1078.004, covering legitimate credentials and weak passwords, as it allows unauthorized access through default or empty credential configurations. The flaw represents a classic case of incomplete input validation and authentication state management, where the system failed to properly enforce required security controls when default parameters were used.
Mitigation strategies should prioritize immediate deployment of version 2.1.4, which addresses the core authentication bypass issue through proper initialization of both authentication handlers. Security practitioners should implement comprehensive monitoring for unauthorized SFTP access attempts and establish strict parameter validation protocols for all goshs deployments. Additionally, operators should avoid using default credential configurations and ensure that all authentication mechanisms are explicitly configured with strong credentials to prevent similar vulnerabilities in other components of the system architecture.