CVE-2002-1581 in mailreader.com
Summary
by MITRE
directory traversal vulnerability in nph-mr.cgi in mailreader.com 2.3.20 through 2.3.31 allows remote attackers to view arbitrary files via .. (dot dot) sequences and a null byte (%00) in the configlanguage parameter.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 09/04/2025
The vulnerability identified as CVE-2002-1581 represents a critical directory traversal flaw in the mailreader.com web application version 2.3.20 through 2.3.31. This vulnerability specifically affects the nph-mr.cgi script which serves as a crucial component for handling mail reader functionalities within the application. The flaw stems from inadequate input validation mechanisms that fail to properly sanitize user-supplied parameters, creating an exploitable condition that allows malicious actors to access files outside the intended directory structure. The vulnerability manifests when attackers manipulate the configlanguage parameter through carefully crafted dot-dot-slash sequences combined with null byte encoding, effectively bypassing normal file access controls and directory restrictions.
From a technical perspective, this directory traversal vulnerability operates by exploiting weak input sanitization in the parameter handling mechanism of the nph-mr.cgi script. When the application processes the configlanguage parameter without proper validation, it fails to strip or escape malicious sequences such as ../.. or %00 characters that would normally be rejected by standard security filters. The combination of dot-dot-slash sequences with null byte encoding creates a sophisticated attack vector that can circumvent path traversal protections implemented by the web application. This technique allows attackers to navigate beyond the intended document root directory and access arbitrary files on the server filesystem, potentially including sensitive configuration files, user credentials, or system files. The vulnerability aligns with CWE-22, which specifically addresses improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal attacks. The attack pattern follows established methodologies described in the MITRE ATT&CK framework under the technique T1083 for discovering system information and T1566 for credential access through various means.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with potential access to sensitive data and system resources that could lead to further exploitation. An attacker could potentially retrieve configuration files containing database credentials, application secrets, or other sensitive information that could be leveraged for additional attacks. The vulnerability's remote nature means that attackers can exploit it from outside the network perimeter without requiring local access or authentication, making it particularly dangerous for web applications exposed to public internet access. The specific version range indicates this was a persistent flaw affecting multiple releases of the mailreader.com application, suggesting that the developers failed to implement proper input validation measures that would have prevented such attacks. This vulnerability could enable attackers to escalate their privileges, access user data, or potentially compromise the entire web server if sensitive files containing system credentials or database access information are accessible through the traversal mechanism.
Effective mitigation strategies for this vulnerability involve implementing robust input validation and sanitization measures that properly filter or escape malicious sequences before they are processed by the application. The most critical remediation is to implement strict parameter validation that rejects or removes sequences such as .., %00, and other potentially dangerous input patterns from user-supplied parameters. Application developers should employ whitelisting approaches for valid input values rather than relying on blacklisting techniques that may miss certain attack vectors. Additionally, the application should be configured to run with minimal privileges and access rights, limiting the potential damage from successful exploitation. Security headers and proper file access controls should be implemented to prevent unauthorized access to sensitive files. The vulnerability highlights the importance of following secure coding practices and input validation principles as outlined in OWASP Top 10 and other security standards. Regular security testing including penetration testing and vulnerability scanning should be conducted to identify similar flaws in other components of the web application. Organizations should also implement proper monitoring and logging to detect and respond to exploitation attempts, as the attack pattern would likely generate suspicious access patterns that could be flagged by intrusion detection systems.