CVE-2002-2211 in BIND
Summary
by MITRE
BIND 4 and BIND 8, when resolving recursive DNS queries for arbitrary hosts, allows remote attackers to conduct DNS cache poisoning via a birthday attack that uses a large number of open queries for the same resource record (RR) combined with spoofed responses, which increases the possibility of successfully spoofing a response in a way that is more efficient than brute force methods.
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Analysis
by VulDB Data Team • 02/06/2025
The vulnerability described in CVE-2002-2211 represents a significant weakness in the Berkeley Internet Name Domain (BIND) software versions 4 and 8, specifically affecting their recursive DNS query resolution capabilities. This flaw enables remote attackers to perform DNS cache poisoning attacks through a sophisticated birthday attack methodology that exploits the predictable nature of DNS query processing. The vulnerability stems from the way BIND handles recursive queries for identical resource records, creating a window of opportunity for malicious actors to manipulate DNS responses through carefully crafted spoofed data. The attack leverages the statistical probability of collision in random number generation to increase the likelihood of successful cache poisoning, making it far more efficient than traditional brute force approaches.
The technical implementation of this vulnerability occurs when BIND servers process multiple recursive queries for the same resource record type, particularly when these queries are initiated by different remote hosts. The birthday attack technique exploits the mathematical principle that in a set of randomly generated values, the probability of finding a collision increases dramatically as the number of samples grows. In the context of DNS resolution, this means that when attackers send numerous open queries for identical resource records, they can manipulate the server's response handling to increase their chances of successfully inserting malicious data into the DNS cache. The flaw is particularly dangerous because it operates at the protocol level where DNS servers maintain state information about ongoing queries and their responses, creating a predictable pattern that attackers can exploit through statistical methods rather than pure randomness.
The operational impact of this vulnerability extends beyond simple cache poisoning, potentially allowing attackers to redirect users to malicious websites, intercept sensitive communications, or disrupt network services entirely. When successful, the attack can compromise the integrity of DNS resolution across the affected network, leading to man-in-the-middle attacks, data exfiltration, or service availability issues. The vulnerability affects systems that rely on recursive DNS resolution for internet connectivity, making it particularly dangerous for enterprise networks, internet service providers, and any organization that depends on stable DNS infrastructure. The attack's efficiency advantage over brute force methods means that even relatively small-scale attacks can achieve success rates that would be prohibitively expensive using traditional approaches, making this vulnerability particularly attractive to malicious actors seeking to compromise DNS infrastructure.
Organizations should implement immediate mitigations including upgrading to newer versions of BIND that address this vulnerability, implementing DNS security extensions such as DNSSEC to provide cryptographic validation of DNS responses, and configuring proper access controls to limit recursive query capabilities. The mitigation strategies should also include monitoring DNS query patterns for unusual activity that might indicate attempted attacks, implementing rate limiting for identical queries, and establishing robust network segmentation to contain potential compromise. From a cybersecurity framework perspective, this vulnerability aligns with CWE-310 and relates to ATT&CK techniques involving DNS tunneling and cache poisoning operations. Network administrators should also consider implementing intrusion detection systems specifically designed to identify DNS cache poisoning attempts and establish incident response procedures to quickly address successful compromises. The vulnerability serves as a critical reminder of the importance of proper random number generation in security-sensitive applications and the necessity of robust cryptographic practices in network protocols.