CVE-2015-8740 in Wireshark
Summary
by MITRE
The dissect_tds7_colmetadata_token function in epan/dissectors/packet-tds.c in the TDS dissector in Wireshark 2.0.x before 2.0.1 does not validate the number of columns, which allows remote attackers to cause a denial of service (stack-based buffer overflow and application crash) via a crafted packet.
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Analysis
by VulDB Data Team • 12/22/2024
The vulnerability identified as CVE-2015-8740 resides within the TDS dissector component of Wireshark, specifically in the dissect_tds7_colmetadata_token function located in epan/dissectors/packet-tds.c. This flaw represents a critical security issue that affects Wireshark versions 2.0.x prior to 2.0.1, where the application fails to properly validate the number of columns contained within TDS protocol packets. The TDS protocol, or Tabular Data Stream, is commonly used for communication between clients and SQL Server databases, making this vulnerability particularly concerning for network monitoring and security analysis environments where Wireshark is extensively deployed.
The technical nature of this vulnerability stems from a stack-based buffer overflow condition that occurs when the dissect_tds7_colmetadata_token function processes malformed TDS packets containing an excessive number of columns. The function does not perform adequate validation checks on the column count parameter, allowing an attacker to craft specially designed packets that exceed the allocated buffer space. When Wireshark attempts to parse these malicious packets, the insufficient bounds checking leads to memory corruption that results in application instability and eventual crash. This behavior aligns with CWE-121, which describes stack-based buffer overflow conditions, and demonstrates how improper input validation can lead to denial of service attacks that compromise application availability.
The operational impact of this vulnerability extends beyond simple application crashes, as it represents a significant threat to network monitoring infrastructure that relies on Wireshark for protocol analysis. Network security teams and analysts who use Wireshark for traffic inspection and forensic analysis face the risk of having their monitoring tools become unavailable when processing malicious traffic. This denial of service condition can occur remotely, meaning that an attacker positioned anywhere on the network can potentially disrupt network analysis operations by sending a single crafted packet. The vulnerability's remote exploitability makes it particularly dangerous in environments where Wireshark is deployed for continuous network monitoring, as it could be used to disrupt security operations or as part of a broader attack campaign targeting network infrastructure.
Mitigation strategies for CVE-2015-8740 primarily focus on immediate version updates to Wireshark 2.0.1 or later, which contain the necessary patches to address the column count validation issue. Network administrators should also implement network segmentation and access controls to limit exposure, while monitoring for suspicious traffic patterns that might indicate exploitation attempts. From an ATT&CK framework perspective, this vulnerability maps to the T1071.004 technique for application layer protocol tunneling, as it represents a method of disrupting network monitoring capabilities. Additionally, organizations should consider implementing network-based intrusion detection systems that can identify and block malformed TDS packets, and maintain regular patch management procedures to ensure all network analysis tools remain up-to-date with security fixes. The vulnerability underscores the importance of robust input validation in network protocol analysis tools, as these applications often process untrusted data from network traffic and must maintain stability even when encountering malformed or malicious packets.