CVE-2007-3159 in MiniWeb Http Server
Summary
by MITRE
http.c in MiniWeb Http Server 0.8.x allows remote attackers to cause a denial of service (application crash) via a negative value in the Content-Length HTTP header.
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Analysis
by VulDB Data Team • 09/20/2024
The vulnerability identified as CVE-2007-3159 affects MiniWeb Http Server version 0.8.x and represents a classic denial of service flaw stemming from inadequate input validation in HTTP header processing. This issue specifically targets the http.c component of the web server software, where the application fails to properly validate the Content-Length header value before processing it. When a remote attacker submits a malformed HTTP request containing a negative value in the Content-Length field, the server encounters a critical processing error that leads to application instability and eventual crash. The vulnerability demonstrates a fundamental lack of proper bounds checking and input sanitization within the HTTP request parsing logic, creating an exploitable condition that can be leveraged by malicious actors to disrupt service availability.
The technical flaw manifests in the server's inability to handle negative integers in the Content-Length header, which should theoretically represent the size of the message body in bytes. When the server attempts to process this negative value, it likely triggers an arithmetic overflow or invalid memory access condition during buffer allocation or data handling operations. This type of vulnerability falls under CWE-191, Integer Underflow (Wrap or Wraparound), as the negative value causes the integer processing to wrap around to a large positive value or null pointer dereference. The root cause lies in the absence of proper validation routines that would reject or normalize negative values before they are processed by the server's core functionality. The vulnerability exploits the server's trust in HTTP header values without sufficient verification, demonstrating poor defensive programming practices that are commonly addressed in secure coding guidelines.
The operational impact of CVE-2007-3159 extends beyond simple service disruption, as it represents a potential vector for broader attack scenarios that align with ATT&CK technique T1499.1, Network Denial of Service. An attacker could repeatedly exploit this vulnerability to maintain sustained service disruption, potentially causing significant business impact through extended downtime and resource consumption during recovery efforts. The vulnerability affects the availability aspect of the CIA triad, specifically targeting the web server's ability to maintain consistent service delivery to legitimate users. Organizations relying on MiniWeb Http Server 0.8.x may experience cascading effects from this denial of service condition, particularly in environments where the server handles critical web applications or serves as a backend component in larger infrastructures. The ease of exploitation makes this vulnerability particularly dangerous as it requires minimal technical expertise to execute against vulnerable systems.
Mitigation strategies for CVE-2007-3159 should prioritize immediate patching of the affected MiniWeb Http Server version, as this represents the most effective solution to address the root cause of the vulnerability. Organizations should implement input validation measures that specifically reject negative values in HTTP headers, particularly Content-Length, through the deployment of web application firewalls or proxy servers that can filter malicious requests before they reach the vulnerable server. Network-level mitigations could include implementing rate limiting and connection throttling to reduce the impact of repeated exploitation attempts. Additionally, system administrators should consider deploying intrusion detection systems that can identify and alert on suspicious Content-Length header values. The vulnerability highlights the importance of implementing comprehensive input validation across all HTTP header processing functions, aligning with security best practices outlined in OWASP Top Ten and NIST Special Publication 800-163 for secure web application development. Regular security assessments and vulnerability scanning should be conducted to identify similar issues in other server components and ensure that all HTTP request handling logic properly validates and sanitizes all input parameters.