CVE-2014-8767 in tcpdump
Summary
by MITRE
Integer underflow in the olsr_print function in tcpdump 3.9.6 through 4.6.2, when in verbose mode, allows remote attackers to cause a denial of service (crash) via a crafted length value in an OLSR frame.
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Analysis
by VulDB Data Team • 02/24/2022
The vulnerability identified as CVE-2014-8767 represents a critical integer underflow flaw within the tcpdump network packet analysis tool. This vulnerability specifically affects versions 3.9.6 through 4.6.2 of tcpdump and manifests when the tool operates in verbose mode. The flaw occurs within the olsr_print function which processes Open Shortest Path First Routing Protocol frames. When tcpdump encounters an OLSR frame with a crafted length value, the integer underflow condition triggers a crash of the application, resulting in a denial of service scenario. The vulnerability stems from inadequate input validation and improper handling of length parameters within the OLSR frame parsing logic.
The technical exploitation of this vulnerability requires an attacker to craft a malicious OLSR frame containing an invalid length field that, when processed by tcpdump in verbose mode, causes the integer underflow to occur. This type of vulnerability falls under the CWE-190 category of integer overflow/underflow, specifically manifesting as an underflow condition that leads to memory corruption. The flaw demonstrates poor defensive programming practices where the application fails to validate that the length field in the OLSR frame remains within acceptable bounds before performing arithmetic operations. When the underflow occurs, it typically results in a negative integer value being used as an array index or loop counter, causing the application to access invalid memory locations and subsequently crash.
The operational impact of this vulnerability extends beyond simple service disruption as it can be leveraged by remote attackers to systematically crash tcpdump instances running in verbose mode. This denial of service condition affects network monitoring and analysis capabilities, potentially disrupting network troubleshooting activities, security audits, and traffic analysis operations that depend on tcpdump functionality. The vulnerability is particularly concerning in environments where tcpdump is used for continuous network monitoring, as attackers could repeatedly exploit this flaw to maintain persistent service disruption. The remote nature of the attack means that adversaries do not require physical access to the target system, making this vulnerability especially dangerous in networked environments where tcpdump is actively processing traffic.
Mitigation strategies for CVE-2014-8767 primarily involve upgrading to tcpdump versions that have patched this vulnerability, specifically versions beyond 4.6.2. Organizations should implement comprehensive patch management procedures to ensure all instances of tcpdump are updated promptly. Additionally, network administrators should consider implementing network segmentation and access controls to limit exposure to potentially malicious OLSR frames. The use of intrusion detection systems that can identify and block malformed OLSR traffic may provide additional protection layers. From a defensive programming perspective, this vulnerability underscores the importance of implementing proper input validation, bounds checking, and integer overflow/underflow protection mechanisms. The ATT&CK framework categorizes this type of vulnerability under the T1499.004 technique for network denial of service, and organizations should consider this when developing their threat modeling and incident response procedures. Regular security assessments and code reviews focusing on integer handling and input validation should be conducted to prevent similar vulnerabilities from emerging in other network analysis tools.