CVE-2002-0613 in DNSTools
Summary
by MITRE
dnstools.php for DNSTools 2.0 beta 4 and earlier allows remote attackers to bypass authentication and gain privileges by setting the user_logged_in or user_dnstools_administrator parameters.
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Analysis
by VulDB Data Team • 09/15/2025
The vulnerability identified as CVE-2002-0613 affects DNSTools 2.0 beta 4 and earlier versions, specifically targeting the dnstools.php script that handles user authentication and authorization. This represents a critical security flaw that undermines the fundamental access control mechanisms of the application. The vulnerability stems from improper input validation and authentication bypass techniques that allow malicious actors to manipulate session parameters without legitimate credentials. The issue manifests when attackers can directly set or modify the user_logged_in or user_dnstools_administrator parameters, effectively granting themselves unauthorized access to administrative functions.
This authentication bypass vulnerability falls under the category of weak session management and improper access control as defined by CWE-285 and CWE-305. The flaw enables attackers to escalate privileges without proper authentication, creating a pathway for unauthorized users to assume administrative roles within the DNSTools application. The vulnerability is particularly concerning because it operates at the application layer, where attackers can manipulate HTTP parameters to gain elevated privileges. The affected parameters user_logged_in and user_dnstools_administrator are typically managed server-side but can be overridden by attackers who directly manipulate these values in their requests.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it allows attackers to perform administrative functions that could compromise the entire DNS infrastructure managed by DNSTools. An attacker who successfully exploits this vulnerability could modify DNS records, add malicious entries, or potentially disrupt network services. The implications are particularly severe in environments where DNS management is critical for network operations, as this vulnerability could lead to complete service disruption or data compromise. The vulnerability's remote exploitability means that attackers do not need physical access or local network presence to exploit the flaw, making it particularly dangerous in publicly accessible environments.
The attack vector for this vulnerability aligns with ATT&CK technique T1078.004 which covers legitimate credentials obtained through deception, as attackers can effectively obtain administrative privileges without proper authentication. The exploitation process involves crafting HTTP requests with modified parameters that bypass normal authentication checks. This vulnerability demonstrates a classic case of insecure parameter handling where user-controllable input directly influences system behavior without proper validation or sanitization. Organizations using affected versions of DNSTools face significant risk of unauthorized modifications to DNS configurations, which could result in service interruptions, data breaches, or redirection attacks. The vulnerability also highlights the importance of implementing proper input validation and secure session management practices to prevent parameter tampering attacks.
Mitigation strategies for CVE-2002-0613 require immediate patching of affected DNSTools versions to address the authentication bypass flaw. Organizations should implement proper parameter validation and ensure that authentication state is managed server-side rather than allowing client-side manipulation of session parameters. The solution involves implementing server-side session management that does not rely on client-controllable variables for authentication decisions. Additionally, organizations should consider implementing network segmentation and access controls to limit exposure to this vulnerability. Regular security audits and input validation testing should be conducted to identify similar vulnerabilities in other applications. The patching process must be prioritized as this vulnerability directly enables privilege escalation and administrative access to critical DNS infrastructure components.