CVE-2018-19626 in Wireshark
Summary
by MITRE
In Wireshark 2.6.0 to 2.6.4 and 2.4.0 to 2.4.10, the DCOM dissector could crash. This was addressed in epan/dissectors/packet-dcom.c by adding '\0' termination.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 06/12/2023
The vulnerability identified as CVE-2018-19626 represents a critical buffer over-read condition affecting Wireshark network protocol analyzers version 2.6.0 through 2.6.4 and 2.4.0 through 2.4.10. This issue resides within the DCOM (Distributed Component Object Model) dissector component responsible for analyzing and interpreting DCOM protocol traffic within network captures. The flaw manifests when processing malformed or specially crafted DCOM packets that exceed expected buffer boundaries during protocol analysis. The vulnerability specifically impacts the epan/dissectors/packet-dcom.c file where the dissector logic fails to properly terminate string buffers before processing incoming data. This improper buffer handling creates a scenario where the dissector attempts to read beyond allocated memory boundaries, leading to unpredictable behavior and potential system instability.
The technical exploitation of this vulnerability occurs through crafted DCOM protocol packets that trigger the buffer over-read condition during packet analysis. When Wireshark processes these malicious packets, the DCOM dissector attempts to access memory locations beyond the intended buffer limits, causing the application to crash or behave unpredictably. This represents a classic buffer over-read vulnerability that aligns with CWE-125, which describes out-of-bounds read conditions in software implementations. The vulnerability is particularly concerning because it can be triggered remotely through network traffic analysis, making it a potential denial-of-service vector that could affect network monitoring systems, security analysts, and forensic investigators who rely on Wireshark for protocol analysis. The fix implemented addresses this issue by adding proper null termination to buffer operations in the dissector code, preventing the over-read condition from occurring.
The operational impact of CVE-2018-19626 extends beyond simple application crashes to potentially compromise network monitoring infrastructure and forensic analysis capabilities. Security professionals and network administrators who depend on Wireshark for traffic analysis may experience unexpected application termination when processing certain network captures containing malformed DCOM traffic. This vulnerability could be exploited by attackers to disrupt network monitoring operations or potentially as part of a broader attack chain where network analysis tools are targeted to prevent incident response activities. The vulnerability also represents a concern for compliance and forensic environments where continuous network monitoring is required, as unexpected application crashes could result in loss of critical network traffic data. Organizations using affected Wireshark versions may experience service disruption during network analysis activities, particularly when processing traffic from vulnerable systems or during security investigations involving DCOM protocol traffic.
Mitigation strategies for this vulnerability require immediate patching of affected Wireshark installations to versions that include the null termination fix in the DCOM dissector. System administrators should prioritize updating all instances of Wireshark across their network monitoring infrastructure, particularly in environments where automated network analysis or security monitoring systems rely on the tool's stability. The vulnerability demonstrates the importance of proper buffer management in protocol dissector implementations, aligning with ATT&CK technique T1059.007 for protocol analysis tools that may be targeted in cyber operations. Organizations should also implement network segmentation and monitoring to detect unusual traffic patterns that might indicate exploitation attempts. Additionally, security teams should consider implementing alternative network analysis tools as part of redundancy planning to ensure continued monitoring capabilities if primary tools become compromised. The vulnerability underscores the critical need for regular security updates and proper input validation in network protocol analysis tools, particularly those handling diverse and potentially malicious network traffic patterns that may be encountered in enterprise environments.