CVE-2001-0457 in man2html
Summary
by MITRE
man2html before 1.5-22 allows remote attackers to cause a denial of service (memory exhaustion).
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Analysis
by VulDB Data Team • 05/26/2019
The vulnerability identified as CVE-2001-0457 affects the man2html utility version 1.5-22 and earlier, presenting a significant security risk that enables remote attackers to execute denial of service attacks through memory exhaustion. This flaw specifically targets the man2html conversion tool that transforms manual pages into html format, which is commonly used in unix and linux environments for documentation generation and web publishing. The vulnerability stems from inadequate input validation and memory management within the conversion process, where maliciously crafted manual page content can trigger excessive memory allocation that ultimately leads to system resource exhaustion.
The technical implementation of this vulnerability involves the man2html utility's handling of certain special characters and formatting sequences within manual pages. When processing malformed input containing recursive or excessively nested structures, the utility fails to properly limit memory allocation, causing it to consume increasing amounts of system memory until the system becomes unresponsive or crashes. This behavior represents a classic memory exhaustion attack pattern that can be exploited remotely through web interfaces or automated systems that utilize man2html for document conversion. The flaw operates at the application level and demonstrates poor resource management practices that are commonly associated with buffer overflow and resource exhaustion vulnerabilities.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromise entire systems or networks that rely on man2html for documentation processing. Attackers can exploit this weakness by submitting specially crafted manual pages or web requests that trigger the memory exhaustion condition, effectively rendering the targeted system unusable for legitimate users. Organizations running web servers, documentation systems, or automated build environments that utilize man2html are particularly at risk, as these systems may be exposed to unauthenticated remote exploitation. The vulnerability can be leveraged as part of broader attack campaigns targeting system availability, making it a critical concern for security administrators managing unix-based environments.
Mitigation strategies for CVE-2001-0457 require immediate patching of affected systems with man2html version 1.5-22 or later, which contains the necessary fixes to prevent excessive memory allocation during document conversion. Security administrators should also implement input validation measures that limit the size and complexity of manual page content processed by man2html, including setting memory limits and timeout parameters for conversion processes. Network-level protections such as firewalls and intrusion detection systems can be configured to monitor for suspicious patterns of man2html usage that might indicate exploitation attempts. Additionally, organizations should consider implementing application-level sandboxes or containers for document conversion processes to isolate potential memory exhaustion effects and prevent system-wide compromise. This vulnerability aligns with CWE-400, which catalogs memory allocation and deallocation issues, and represents a clear example of how insufficient resource management can create availability risks that attackers can exploit for system disruption.