CVE-2002-0400 in BIND
Summary
by MITRE
ISC BIND 9 before 9.2.1 allows remote attackers to cause a denial of service (shutdown) via a malformed DNS packet that triggers an error condition that is not properly handled when the rdataset parameter to the dns_message_findtype() function in message.c is not NULL, aka DoS_findtype.
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Analysis
by VulDB Data Team • 06/18/2024
The vulnerability identified as CVE-2002-0400 represents a critical denial of service flaw within ISC BIND 9.0.x and 9.1.x versions prior to 9.2.1. This vulnerability specifically targets the dns_message_findtype() function in the message.c source file, where improper error handling occurs when processing malformed DNS packets. The flaw exploits a condition where the rdataset parameter is not properly validated, creating an opportunity for remote attackers to disrupt DNS service operations. The vulnerability operates at the core of DNS message processing, making it particularly dangerous as it can compromise the fundamental network infrastructure services that depend on BIND resolver functionality.
The technical implementation of this vulnerability stems from inadequate input validation within the dns_message_findtype() function, which is responsible for locating specific resource record types within DNS messages. When a malformed DNS packet is received with an improperly structured rdataset parameter, the function fails to handle the error condition gracefully. This error condition manifests as an unhandled exception that causes the BIND server process to terminate unexpectedly, resulting in complete service disruption. The vulnerability specifically affects versions where the rdataset parameter is not NULL, indicating that the flaw occurs during normal processing of DNS messages rather than during initialization or cleanup phases. This characteristic makes the vulnerability particularly insidious as it can be triggered through routine DNS traffic rather than requiring specialized attack vectors.
The operational impact of CVE-2002-0400 extends beyond simple service disruption to encompass broader network reliability concerns. When exploited, the vulnerability can cause complete DNS server shutdown, affecting all domains and services dependent on that particular DNS infrastructure. Network administrators face the challenge of maintaining service availability while the vulnerable server is offline, potentially affecting thousands of users and applications that rely on DNS resolution. The vulnerability's remote exploitability means that attackers can trigger the denial of service from anywhere on the internet without requiring local access or authentication credentials, making it particularly attractive for attackers seeking to disrupt network services. This characteristic aligns with ATT&CK technique T1499.004 for network denial of service attacks and maps to CWE-248 for an exception is thrown from a constructor or destructor.
Mitigation strategies for CVE-2002-0400 focus primarily on immediate software updates to BIND versions 9.2.1 and later, which contain the necessary patches to properly handle the error conditions. Organizations should implement comprehensive patch management procedures to ensure all DNS servers are updated promptly, as the vulnerability affects core infrastructure components. Additionally, network administrators can implement temporary protective measures such as rate limiting DNS queries, implementing access control lists to restrict DNS traffic sources, and deploying intrusion detection systems to monitor for suspicious DNS packet patterns. The vulnerability's classification under CWE-248 and its exploitation pattern align with ATT&CK framework's focus on system exploitation techniques, particularly those involving application-level vulnerabilities that can be leveraged for service disruption. Organizations should also consider implementing redundant DNS infrastructure to provide failover capabilities during vulnerability remediation periods, ensuring continued service availability while addressing the underlying security flaw.