CVE-2001-0013 in BIND
Summary
by MITRE
Format string vulnerability in nslookupComplain function in BIND 4 allows remote attackers to gain root privileges.
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Analysis
by VulDB Data Team • 06/12/2024
The vulnerability identified as CVE-2001-0013 represents a critical format string flaw within the nslookupComplain function of BIND 4, a widely deployed Domain Name System implementation that served as the foundation for internet domain resolution services. This vulnerability specifically affects the nslookup utility component of BIND 4, which was commonly used for querying DNS server information and resolving domain names. The flaw exists in how the application processes user-supplied input when generating error messages, creating a pathway for malicious input to be interpreted as format specifiers rather than literal text. The vulnerability stems from improper input validation and handling within the nslookupComplain function, where error messages containing user-provided data are passed directly to printf-style functions without proper sanitization, creating an exploitable condition that allows attackers to manipulate memory contents through carefully crafted input sequences.
The technical exploitation of this vulnerability requires an attacker to provide malicious input that contains format specifiers such as %s, %d, or %x, which when processed by the vulnerable printf function can result in reading arbitrary memory locations or writing data to specific memory addresses. The root privilege escalation occurs because the nslookup utility, when executed with elevated privileges, processes the malformed input through the vulnerable function, allowing the attacker to manipulate the program execution flow and potentially execute arbitrary code with the privileges of the running process. This particular vulnerability aligns with CWE-134, which specifically addresses the use of format strings with user-supplied data, and represents a classic example of how improper input handling can lead to privilege escalation and arbitrary code execution. The vulnerability operates under the principle that when printf or similar functions receive user-controllable data as format arguments, attackers can exploit the format string processing to extract memory contents or modify program behavior.
The operational impact of this vulnerability extends far beyond simple privilege escalation, as it fundamentally compromises the security of DNS infrastructure and can be leveraged in broader attack scenarios. Attackers can utilize this vulnerability to gain unauthorized access to systems running vulnerable versions of BIND 4, potentially leading to complete system compromise and control over DNS resolution services. The implications are particularly severe given that BIND 4 was widely deployed across internet infrastructure, making this vulnerability a significant threat vector that could affect numerous systems simultaneously. This vulnerability also aligns with ATT&CK technique T1059, which covers command and script interpretation, as successful exploitation could allow attackers to execute arbitrary commands on compromised systems. The vulnerability's potential for remote exploitation without authentication makes it especially dangerous in networked environments where DNS services are accessible to untrusted users.
Mitigation strategies for CVE-2001-0013 must address both immediate remediation and long-term security posture improvements. The primary solution involves upgrading to a patched version of BIND that properly sanitizes input before processing, as the vulnerability was resolved in subsequent releases of the software. Organizations should implement input validation measures that prevent format specifiers from being processed as literal data, and where possible, use safer alternatives to printf functions such as snprintf or fprintf with proper length constraints. System administrators should also consider implementing network segmentation and access controls to limit exposure of vulnerable DNS services to untrusted networks. Additionally, regular security auditing and penetration testing should be conducted to identify similar vulnerabilities in other network services, as this vulnerability demonstrates the importance of proper input validation and secure coding practices. The remediation process should include thorough testing of patched software to ensure that the vulnerability is fully resolved without introducing new issues, and organizations should maintain updated inventory records of all systems running vulnerable versions of BIND to facilitate rapid response to similar future vulnerabilities.