CVE-2023-6174 in Wireshark
Summary
by MITRE • 11/16/2023
SSH dissector crash in Wireshark 4.0.0 to 4.0.10 allows denial of service via packet injection or crafted capture file
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Analysis
by VulDB Data Team • 04/21/2025
The vulnerability identified as CVE-2023-6174 represents a critical denial of service flaw within Wireshark's SSH dissector component affecting versions 4.0.0 through 4.0.10. This issue arises from improper handling of specific SSH protocol packets during packet analysis, creating a scenario where maliciously crafted network traffic or capture files can trigger a complete application crash. The vulnerability specifically targets the SSH dissector module responsible for parsing and interpreting Secure Shell protocol communications, which is fundamental to network forensics and security analysis operations.
The technical flaw manifests when Wireshark processes SSH packets containing malformed or unexpected data structures within the protocol's packet headers or payload sections. The dissector fails to properly validate input parameters before attempting to parse SSH protocol elements, leading to memory corruption or invalid pointer dereferences that ultimately cause the application to terminate unexpectedly. This behavior aligns with CWE-121, which describes heap-based buffer overflow conditions, and CWE-125, which covers out-of-bounds read vulnerabilities that can occur when insufficient bounds checking is performed on input data.
From an operational perspective, this vulnerability presents significant risk to network security analysts and forensic investigators who rely on Wireshark for network traffic analysis. Attackers can exploit this flaw by either injecting malicious SSH packets into network traffic or by crafting specially formatted capture files that, when opened in Wireshark, will trigger the crash. The impact extends beyond simple application termination as it can disrupt ongoing network monitoring operations, potentially masking malicious activities during the time when the application is unavailable. This vulnerability directly maps to ATT&CK technique T1499.001, which involves network disruption through denial of service attacks, and T1566.001, covering spearphishing attacks that could leverage such vulnerabilities.
The exploitation of CVE-2023-6174 demonstrates the critical importance of input validation in network protocol analysis tools. Security professionals using Wireshark for network monitoring, incident response, and security auditing operations face potential operational disruption when this vulnerability is present in their environment. The vulnerability's impact is particularly concerning given that Wireshark is widely used across enterprise security operations centers, forensic laboratories, and network administration teams where continuous network monitoring is essential for security posture maintenance. Organizations should implement immediate mitigation strategies including upgrading to patched versions of Wireshark, implementing network segmentation to limit exposure, and establishing monitoring protocols to detect potential exploitation attempts. The vulnerability underscores the necessity of maintaining up-to-date security tools and implementing robust patch management processes to protect against known exploits that could compromise network monitoring capabilities and security infrastructure.