CVE-2001-0433 in Savant Webserver
Summary
by MITRE
Buffer overflow in Savant 3.0 web server allows remote attackers to cause a denial of service, and possibly execute arbitrary commands, via a long Host HTTP header.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 05/18/2019
The vulnerability identified as CVE-2001-0433 represents a critical buffer overflow flaw within the Savant 3.0 web server implementation that exposes systems to remote exploitation. This vulnerability specifically targets the handling of HTTP Host headers, which are fundamental components of web communication protocols. The flaw occurs when the web server processes excessively long Host header values without proper input validation or bounds checking, creating an exploitable condition where attacker-controlled data can overwrite adjacent memory regions. Such buffer overflow conditions are particularly dangerous because they can lead to unpredictable system behavior and potential code execution.
The technical implementation of this vulnerability stems from improper memory management within the Savant web server's HTTP header parsing routine. When a client sends a malformed Host header containing more data than the allocated buffer can accommodate, the excess data overflows into adjacent memory locations, potentially corrupting critical program state information or executable code segments. This type of vulnerability falls under CWE-121, which categorizes buffer overflow conditions where insufficient bounds checking allows memory corruption. The attack vector is particularly concerning as it requires no authentication or privileged access, making it a classic example of a remote code execution vulnerability that can be exploited over the network.
The operational impact of CVE-2001-0433 extends beyond simple denial of service scenarios to include potential arbitrary code execution capabilities. While the vulnerability description mentions denial of service as a primary concern, the buffer overflow nature suggests that sophisticated attackers could potentially craft malicious Host headers that overwrite function return addresses or other critical program structures, enabling remote command execution. This represents a significant threat to web server availability and system integrity, as compromised servers could be used as launching points for further attacks within network infrastructures. The vulnerability's exploitation aligns with ATT&CK technique T1210 which covers exploitation of remote services through buffer overflow attacks.
Mitigation strategies for this vulnerability require immediate implementation of software updates or patches provided by the vendor, as the flaw exists within the core web server functionality. Organizations should implement network-level protections such as intrusion detection systems that can identify and block suspicious Host header patterns, particularly those exceeding normal length parameters. Input validation measures should be deployed at network boundaries to filter out excessively long Host headers before they reach the vulnerable web server. Additionally, system administrators should consider implementing application-level firewalls or web application firewalls that can monitor and sanitize HTTP headers to prevent buffer overflow exploitation attempts. The vulnerability demonstrates the critical importance of proper input validation and bounds checking in server-side applications, reinforcing industry best practices outlined in secure coding standards that emphasize defensive programming techniques to prevent memory corruption vulnerabilities.