CVE-2001-0849 in Viralator
Summary
by MITRE
viralator CGI script in Viralator 0.9pre1 and earlier allows remote attackers to execute arbitrary code via a URL for a file being downloaded, which is insecurely passed to a call to wget.
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Analysis
by VulDB Data Team • 10/02/2025
The vulnerability identified as CVE-2001-0849 represents a critical security flaw in the Viralator web application version 0.9pre1 and earlier. This issue resides within the viralator CGI script which processes user-supplied URLs for file downloads. The vulnerability stems from improper input validation and insecure handling of user-provided data, creating a pathway for remote code execution attacks. The flaw specifically manifests when the application accepts a URL parameter and directly passes it to the wget command without adequate sanitization or validation, effectively allowing malicious actors to inject arbitrary commands that get executed on the server.
This vulnerability operates at the intersection of multiple security domains including command injection and insecure input handling, aligning with CWE-78 which describes improper neutralization of special elements used in OS commands. The technical implementation involves the CGI script receiving a URL parameter and passing it directly to the system shell through wget, creating a classic command injection scenario. Attackers can exploit this by crafting malicious URLs containing shell metacharacters and commands that get executed with the privileges of the web server process, potentially leading to complete system compromise.
The operational impact of this vulnerability is severe and far-reaching within the affected environment. Remote attackers can execute arbitrary code on the vulnerable system, potentially gaining full control over the server, accessing sensitive data, establishing persistent backdoors, or using the compromised system as a launch point for further attacks against network infrastructure. The vulnerability affects any system running Viralator 0.9pre1 or earlier versions where the CGI script is accessible, making it particularly dangerous in production environments where such applications may be exposed to untrusted users or attackers.
Mitigation strategies for CVE-2001-0849 should focus on immediate remediation through software updates to versions that address the command injection vulnerability. Organizations should implement proper input validation and sanitization techniques that prevent special characters from being passed to system commands, utilizing parameterized interfaces or command execution libraries that properly escape user input. The implementation of web application firewalls and input filtering mechanisms can provide additional protection layers. Security best practices dictate that all user-supplied input should be validated against a whitelist of acceptable characters and patterns, with any potentially dangerous sequences being rejected or properly escaped before processing. Organizations should also consider implementing least privilege principles for web server processes and regularly audit their systems for outdated software versions that may contain known vulnerabilities. This vulnerability exemplifies the importance of secure coding practices and input validation in preventing command injection attacks, with implications for the broader security community's understanding of CGI security vulnerabilities and their remediation approaches.