CVE-2007-0158 in thttpd
Summary
by MITRE
thttpd 2007 has buffer underflow.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 03/17/2024
The vulnerability identified as CVE-2007-0158 affects thttpd version 2007, a lightweight web server implementation that has been widely used in embedded systems and network appliances. This buffer underflow represents a critical security flaw that can potentially allow remote attackers to execute arbitrary code or cause denial of service conditions. The vulnerability stems from improper input validation within the web server's handling of HTTP requests, specifically when processing certain malformed headers or parameters that exceed allocated buffer boundaries. The flaw occurs during the parsing of client requests where thttpd fails to properly bounds-check data before copying it into fixed-size memory buffers, creating conditions where attacker-controlled data can overwrite adjacent memory locations. This type of vulnerability falls under the Common Weakness Enumeration category CWE-121, which encompasses buffer overflow and underflow conditions that occur when data is written beyond the boundaries of a fixed-length buffer. The attack vector for this vulnerability is primarily remote, as it can be exploited through HTTP requests sent to the vulnerable web server instance. An attacker could craft malicious HTTP requests containing oversized headers or parameters that trigger the buffer underflow condition. When the web server processes these malformed requests, the underflow can corrupt memory layout, potentially leading to execution of arbitrary code with the privileges of the web server process. The operational impact of this vulnerability extends beyond simple denial of service, as successful exploitation could result in complete system compromise, especially when the web server runs with elevated privileges. The vulnerability is particularly concerning in embedded environments where thttpd is commonly deployed, as these systems often have limited security monitoring capabilities and may be difficult to patch promptly. The attack surface is broad since thttpd is used in various network devices including routers, firewalls, and IoT appliances where web interfaces are provided for management purposes. The exploitability of this vulnerability requires that the attacker can send HTTP requests to the target server, which is typically feasible in network environments where the web server is accessible to untrusted clients. From an enterprise security perspective, this vulnerability aligns with ATT&CK technique T1210, which involves exploitation of remote services to gain unauthorized access, and T1068, which covers local privilege escalation through exploitation of software vulnerabilities. Organizations using thttpd version 2007 should prioritize patching or implementing network segmentation to isolate vulnerable instances, as the vulnerability can be exploited without authentication in many scenarios. The remediation approach should include upgrading to a patched version of thttpd, implementing input validation at the network level, and deploying intrusion detection systems to monitor for suspicious HTTP request patterns that may indicate exploitation attempts. Additionally, system administrators should consider disabling unnecessary web interfaces on network devices and implementing proper access controls to limit exposure to potential attackers. The vulnerability demonstrates the importance of proper input validation and bounds checking in network service implementations, highlighting how seemingly minor coding errors can create significant security risks in widely deployed software components.