CVE-2004-0807 in Samba
Summary
by MITRE
Samba 3.0.6 and earlier allows remote attackers to cause a denial of service (infinite loop and memory exhaustion) via certain malformed requests that cause new processes to be spawned and enter an infinite loop.
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Analysis
by VulDB Data Team • 03/09/2021
The vulnerability identified as CVE-2004-0807 represents a critical denial of service flaw within Samba versions 3.0.6 and earlier. This weakness specifically targets the file sharing and authentication services provided by Samba, which operates as a middleware solution enabling interoperability between unix-like systems and windows environments. The vulnerability arises from insufficient input validation mechanisms within the Samba server implementation, particularly when processing certain network requests that trigger process creation and subsequent execution loops.
The technical exploitation of this vulnerability occurs when remote attackers send malformed requests to the Samba service, which then causes the server to spawn new processes that become trapped in infinite loops. This design flaw creates a cascading effect where each malformed request generates additional processes that consume system resources without termination. The infinite loop mechanism prevents proper process cleanup and resource management, leading to progressive memory exhaustion across the affected system. The flaw essentially creates a resource starvation condition where legitimate system operations become impossible due to the overwhelming consumption of available memory and cpu cycles.
From an operational perspective, this vulnerability presents a severe risk to network infrastructure relying on Samba services for file sharing and authentication. Organizations utilizing affected Samba versions face potential disruption of critical business operations, including complete service outages for file servers, print services, and domain authentication functions. The impact extends beyond simple service interruption as the memory exhaustion can cause system instability, application crashes, and potentially complete system hangs. Network administrators may find themselves unable to access critical file shares or authenticate users, leading to productivity losses and operational downtime that can span hours or days depending on the recovery process.
The vulnerability aligns with CWE-400, which categorizes it as a weakness related to resource exhaustion, specifically manifesting as an infinite loop that consumes system resources. From an attack framework perspective, this flaw maps to several ATT&CK techniques including T1499.004 for network denial of service and T1566.001 for spearphishing with social engineering. The vulnerability demonstrates poor input validation practices that should be addressed through proper request parsing and resource management protocols. Organizations should implement immediate mitigation strategies including patching to Samba version 3.0.7 or later, implementing network access controls to restrict unauthorized access to Samba services, and establishing monitoring systems to detect unusual process spawning patterns. Additionally, system administrators should configure resource limits and process monitoring to detect and automatically terminate malicious processes before they can exhaust system resources, ensuring continued availability of critical services while maintaining proper security controls.