CVE-2004-0815 in Samba
Summary
by MITRE
The unix_clean_name function in Samba 2.2.x through 2.2.11, and 3.0.x before 3.0.2a, trims certain directory names down to absolute paths, which could allow remote attackers to bypass the specified share restrictions and read, write, or list arbitrary files via "/.////" style sequences in pathnames.
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Analysis
by VulDB Data Team • 07/07/2025
The vulnerability described in CVE-2004-0815 represents a critical path traversal flaw within the Samba file sharing implementation that affected versions ranging from 2.2.x through 2.2.11 and specific 3.0.x releases prior to 3.0.2a. This security weakness resides in the unix_clean_name function which processes directory names and path normalization within the Samba server's file system operations. The flaw enables malicious actors to manipulate file paths through carefully crafted sequences containing multiple forward slashes and dots that ultimately bypass intended share restrictions. The vulnerability operates at the core of Samba's path handling mechanism, where the function fails to properly validate or sanitize directory name sequences before processing them for file system access operations.
The technical implementation of this vulnerability stems from inadequate input validation within the unix_clean_name function's path normalization logic. When processing pathnames containing "/.////" style sequences, the function incorrectly interprets these complex path structures and reduces them to absolute paths that circumvent the normal share restriction mechanisms. This occurs because the path trimming process does not properly account for multiple consecutive slashes and dot components that should be normalized to prevent access to restricted directories. The flaw essentially allows attackers to construct path sequences that appear to reference specific share locations while actually resolving to arbitrary file system locations outside the intended boundaries. This behavior violates fundamental security principles of access control and path isolation that are essential for network file sharing services.
The operational impact of this vulnerability extends far beyond simple unauthorized file access, as it provides attackers with the capability to read, write, and list arbitrary files on the affected system. Attackers can exploit this weakness to bypass share-level restrictions entirely, potentially gaining access to sensitive system files, user data, or other restricted resources that should be protected by the Samba configuration. The vulnerability enables privilege escalation scenarios where remote attackers can access files that would normally be restricted to specific users or groups within the share structure. This represents a severe compromise of the integrity and confidentiality of network file sharing environments, particularly in enterprise settings where Samba servers typically manage critical file access controls and user permissions. The vulnerability's impact is amplified because it affects multiple versions of Samba, making it a widespread concern for organizations maintaining legacy file sharing infrastructure.
Organizations should implement immediate mitigations including updating to patched versions of Samba where available, specifically versions 2.2.12 and 3.0.2a or later that contain the necessary fixes for this path traversal vulnerability. Network segmentation and access controls should be strengthened to limit exposure of vulnerable Samba instances, while monitoring systems should be configured to detect unusual path traversal patterns in file access logs. The vulnerability aligns with CWE-22 Path Traversal and CWE-352 Cross-Site Request Forgery patterns, and represents a technique commonly catalogued in ATT&CK framework under T1059 Command and Scripting Interpreter and T1566 Phishing with Malicious Attachments, as attackers often leverage such vulnerabilities to gain unauthorized system access. Administrators should also consider implementing additional security controls such as mandatory access controls, file system permissions, and regular security audits to prevent exploitation of similar path handling vulnerabilities in other network services.