CVE-2000-1026 in tcpdump
Summary
by MITRE
Multiple buffer overflows in LBNL tcpdump allow remote attackers to execute arbitrary commands.
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Analysis
by VulDB Data Team • 01/30/2025
The vulnerability identified as CVE-2000-1026 represents a critical security flaw in the tcpdump network packet analysis tool developed by the Lawrence Berkeley National Laboratory. This issue affects versions of tcpdump prior to 3.0.2 and stems from multiple buffer overflow conditions that occur when processing specially crafted network packets. The vulnerability is particularly dangerous because it allows remote attackers to execute arbitrary commands on systems running vulnerable versions of tcpdump, effectively granting them complete control over the affected machine. The tcpdump utility is widely used for network monitoring and analysis, making this vulnerability a significant threat to network security infrastructure.
The technical implementation of this vulnerability involves buffer overflow conditions in the packet parsing functions within tcpdump. When the tool processes malformed network packets containing overly long strings or specially crafted data structures, it fails to properly validate input lengths before copying data into fixed-size buffers. This classic buffer overflow occurs in multiple locations within the tcpdump codebase, including functions that handle various network protocols and packet formats. The overflow allows attackers to overwrite adjacent memory locations, potentially including return addresses on the stack, which can be manipulated to redirect program execution to malicious code. The vulnerability is classified under CWE-121 as a stack-based buffer overflow, which is a well-documented weakness in software development practices where insufficient bounds checking leads to memory corruption.
The operational impact of CVE-2000-1026 is severe and far-reaching across network security environments. Attackers can exploit this vulnerability from remote locations without requiring authentication, making it particularly dangerous for systems that run tcpdump in monitoring mode. The ability to execute arbitrary commands means that attackers can gain full system access, install backdoors, modify system files, or use the compromised system as a launch point for further attacks. This vulnerability directly maps to attack techniques described in the MITRE ATT&CK framework under the T1059.007 technique for command and scripting interpreter, specifically focusing on the execution of arbitrary code through buffer overflow exploits. The vulnerability also relates to T1046 network service scanning and T1566 credential access techniques, as compromised systems can be used for lateral movement and privilege escalation.
Systems most at risk include network monitoring servers, security appliances, and any devices running vulnerable versions of tcpdump in promiscuous mode or as part of network security toolchains. The vulnerability affects Unix-like operating systems where tcpdump is commonly deployed, including various versions of Linux, BSD, and Solaris. Organizations using tcpdump for network traffic analysis, intrusion detection, or security auditing are particularly vulnerable since these tools are often run with elevated privileges to capture network packets. The exploitability of this vulnerability is high due to the widespread use of tcpdump and the minimal prerequisites required for successful exploitation. Security professionals should note that this vulnerability was patched in tcpdump version 3.0.2, making it essential for organizations to maintain up-to-date network security tools and conduct regular vulnerability assessments.
Mitigation strategies for CVE-2000-1026 require immediate patching of all affected tcpdump installations, as this vulnerability has been widely exploited in the wild since its disclosure. Organizations should implement network segmentation and access controls to limit the exposure of systems running tcpdump, particularly those in monitoring or auditing roles. Network administrators should consider disabling tcpdump on systems where it is not essential for security operations, or implementing additional input validation and bounds checking measures. The vulnerability highlights the importance of secure coding practices and input validation, as recommended in the OWASP Secure Coding Practices. Regular security audits and penetration testing should include verification of tcpdump versions and configuration to ensure that systems are not running vulnerable software. Additionally, implementing network monitoring solutions that can detect and prevent exploitation attempts, such as intrusion detection systems with signature-based detection, can provide additional layers of protection against this type of attack.