CVE-2011-1959 in Wireshark
Summary
by MITRE
The snoop_read function in wiretap/snoop.c in Wireshark 1.2.x before 1.2.17 and 1.4.x before 1.4.7 does not properly handle certain virtualizable buffers, which allows remote attackers to cause a denial of service (application crash) via a large length value in a snoop file that triggers a stack-based buffer over-read.
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Analysis
by VulDB Data Team • 11/08/2021
The vulnerability identified as CVE-2011-1959 represents a critical stack-based buffer over-read flaw within Wireshark's snoop file parsing functionality. This issue affects versions 1.2.x prior to 1.2.17 and 1.4.x prior to 1.4.7, where the snoop_read function in wiretap/snoop.c fails to properly validate buffer boundaries when processing virtualizable buffers. The flaw occurs specifically when handling large length values within snoop files, creating a condition where the application attempts to read beyond allocated memory boundaries.
The technical implementation of this vulnerability stems from inadequate input validation within the snoop file parser, which processes network capture files in the snoop format. When a maliciously crafted snoop file contains an excessively large length field, the snoop_read function does not perform proper bounds checking before accessing buffer memory locations. This oversight creates a classic stack-based buffer over-read condition where the application reads data from memory locations beyond the intended buffer boundaries, potentially accessing uninitialized memory or memory belonging to other variables.
From an operational perspective, this vulnerability presents a significant denial of service risk that can be exploited remotely by attackers who craft malicious snoop files. The impact manifests as application crashes that can be triggered simply by opening or processing a specially crafted snoop file within Wireshark. This makes the vulnerability particularly dangerous in environments where users might unknowingly open network capture files from untrusted sources, as the crash occurs during normal file processing operations rather than requiring complex exploitation techniques. The vulnerability aligns with CWE-121 stack-based buffer overflow classification and can be categorized under ATT&CK technique T1059.007 for application execution via file processing.
The remediation for this vulnerability requires updating to Wireshark versions 1.2.17 or 1.4.7 and later, which contain proper bounds checking implementations in the snoop file parser. Organizations should implement immediate patch management procedures to upgrade affected systems and consider deploying network monitoring solutions that can detect and prevent the execution of potentially malicious snoop files. Additionally, system administrators should establish strict file validation protocols for network capture files, particularly those received from external sources or untrusted networks. The vulnerability demonstrates the importance of robust input validation in network analysis tools and highlights how seemingly benign file format parsing can become a vector for application instability and potential system compromise.