CVE-2017-6014 in Wireshark
Summary
by MITRE
In Wireshark 2.2.4 and earlier, a crafted or malformed STANAG 4607 capture file will cause an infinite loop and memory exhaustion. If the packet size field in a packet header is null, the offset to read from will not advance, causing continuous attempts to read the same zero length packet. This will quickly exhaust all system memory.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 02/17/2017
The vulnerability identified as CVE-2017-6014 represents a critical memory exhaustion flaw in Wireshark versions 2.2.4 and earlier, specifically affecting the handling of STANAG 4607 capture files. This vulnerability stems from inadequate input validation and error handling within the packet processing engine, where the software fails to properly validate packet headers before attempting to parse their contents. The flaw manifests when processing malformed STANAG 4607 files, which are military standard format capture files used for exchanging network traffic data. When a packet size field contains a null value, the parsing logic becomes trapped in an infinite loop as the read offset fails to advance properly, continuously attempting to process the same zero-length packet.
The technical implementation of this vulnerability directly relates to CWE-835, which describes the weakness of an infinite loop or infinite recursion in software systems. The flaw operates through a classic buffer over-read scenario where the packet header parsing routine does not properly validate that the packet size field contains a valid non-zero value before proceeding with the read operation. This creates a condition where the offset variable remains static while the parsing algorithm continuously attempts to process the same packet, leading to exponential memory consumption. The STANAG 4607 format specification defines specific packet structures that Wireshark must correctly interpret, but the vulnerability occurs when these structures are malformed or contain invalid data that the parser cannot handle gracefully.
From an operational perspective, this vulnerability presents a severe denial-of-service risk that can be exploited by attackers who craft malicious capture files. The infinite loop behavior causes rapid memory exhaustion, potentially leading to system crashes, application hangs, or complete system instability. Network security analysts and forensic investigators who rely on Wireshark for packet analysis are particularly vulnerable, as simply opening a maliciously crafted capture file can compromise their systems. The attack vector is relatively simple to execute, requiring only the creation of a malformed STANAG 4607 file with a null packet size field, making it a high-risk vulnerability for environments where untrusted capture files might be processed. This vulnerability also aligns with ATT&CK technique T1499.001, which describes resource exhaustion attacks targeting software applications through malformed inputs.
The mitigation strategy for CVE-2017-6014 involves immediate patching of Wireshark to versions 2.2.5 or later, where the developers implemented proper input validation and boundary checks for packet size fields. Organizations should also implement network segmentation and access controls to limit exposure to potentially malicious capture files, while establishing strict file validation procedures for any packet capture data. Additionally, security monitoring should include detection of unusual memory consumption patterns in network analysis tools, and regular security audits should verify that all network forensic tools are updated to their latest secure versions. The vulnerability demonstrates the critical importance of robust input validation and error handling in network security tools, where a single malformed input can lead to complete system compromise.