CVE-2003-0201 in Samba
Summary
by MITRE
Buffer overflow in the call_trans2open function in trans2.c for Samba 2.2.x before 2.2.8a, 2.0.10 and earlier 2.0.x versions, and Samba-TNG before 0.3.2, allows remote attackers to execute arbitrary code.
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Analysis
by VulDB Data Team • 01/21/2025
The vulnerability identified as CVE-2003-0201 represents a critical buffer overflow condition within the Samba file sharing implementation that affects multiple versions of the Samba software suite. This flaw exists in the call_trans2open function located in the trans2.c source file, which is part of the core SMB/CIFS protocol handling mechanisms. The vulnerability specifically impacts Samba versions 2.2.x prior to 2.2.8a, 2.0.x versions earlier than 2.0.10, and Samba-TNG versions before 0.3.2, making it one of the more widespread buffer overflow issues in the Samba ecosystem during that era.
The technical nature of this buffer overflow stems from insufficient input validation and bounds checking within the trans2.c file when processing certain SMB protocol requests. When a remote attacker sends a specially crafted SMB request containing overly long data in specific fields, the call_trans2open function fails to properly validate the buffer sizes, leading to memory corruption that can be exploited to overwrite adjacent memory locations. This particular implementation flaw falls under CWE-121, which describes "Stack-based Buffer Overflow" conditions where insufficient bounds checking allows attackers to overwrite stack data. The vulnerability is particularly dangerous because it allows for arbitrary code execution, meaning that an attacker could potentially gain complete control over the affected Samba server.
The operational impact of CVE-2003-0201 extends far beyond simple denial of service scenarios, as the remote code execution capability provides attackers with complete system compromise potential. Organizations running vulnerable Samba servers face significant risks including unauthorized data access, privilege escalation, backdoor installation, and potential use as a launching point for further attacks within the network infrastructure. The vulnerability affects systems that rely on Samba for file sharing services, particularly in enterprise environments where Windows file sharing interoperability is required. This flaw particularly impacts Unix and Linux systems that implement Samba as their file sharing solution, making it a critical concern for system administrators managing mixed operating system environments. The attack vector requires only network connectivity to the affected Samba service, making it highly exploitable in both internal and external network scenarios.
The exploitation of this vulnerability aligns with several techniques documented in the MITRE ATT&CK framework, particularly under the T1059.007 technique for "Command and Scripting Interpreter: PowerShell" and T1068 for "Exploitation for Privilege Escalation." Security professionals should implement immediate mitigations including applying the appropriate security patches released by the Samba development team, which addressed the buffer overflow by implementing proper bounds checking and input validation. Organizations should also consider network segmentation, firewall rules to restrict SMB service access, and monitoring for suspicious SMB protocol activity. The vulnerability demonstrates the critical importance of input validation in network services and highlights why proper bounds checking should be implemented as fundamental security controls in all network protocol implementations. Additionally, system administrators should conduct thorough vulnerability assessments to identify any other potentially affected systems and ensure that all Samba installations are updated to versions that contain the necessary security patches to prevent exploitation of this and similar buffer overflow vulnerabilities.