CVE-2016-5356 in Wireshark
Summary
by MITRE
wiretap/cosine.c in the CoSine file parser in Wireshark 1.12.x before 1.12.12 and 2.x before 2.0.4 mishandles sscanf unsigned-integer processing, which allows remote attackers to cause a denial of service (application crash) via a crafted file.
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Analysis
by VulDB Data Team • 09/13/2022
The vulnerability identified as CVE-2016-5356 represents a critical denial of service flaw within Wireshark's CoSine file parsing functionality. This issue specifically affects the wiretap/cosine.c component of Wireshark's packet analysis suite, where improper handling of sscanf operations during unsigned integer processing creates a pathway for remote exploitation. The vulnerability exists in Wireshark versions 1.12.x prior to 1.12.12 and 2.x versions prior to 2.0.4, making it a widespread concern across multiple release lines of the popular network protocol analyzer.
The technical root cause of this vulnerability stems from how the sscanf function processes unsigned integer values within the CoSine file parser. When processing malformed or crafted input files, the sscanf operation fails to properly validate or handle unsigned integer conversions, leading to unpredictable behavior in the application's memory management. This improper handling creates conditions where the application can encounter buffer overflows, memory corruption, or other critical state violations that result in application termination. The vulnerability specifically exploits the difference between signed and unsigned integer processing within the sscanf function, where unsigned values may not be properly constrained or validated against expected ranges.
From an operational perspective, this vulnerability poses significant risk to network security analysts and forensic investigators who rely on Wireshark for packet analysis and network troubleshooting. Remote attackers can craft malicious CoSine files that, when opened by an affected Wireshark version, will trigger an application crash and subsequent denial of service. This means that any system running vulnerable Wireshark versions could be compromised simply by opening a maliciously crafted file, potentially disrupting network monitoring operations, forensic analysis, or security incident response activities. The impact extends beyond individual systems to potentially affect entire network monitoring infrastructures that depend on Wireshark for critical operations.
The vulnerability aligns with CWE-121, which addresses stack-based buffer overflow conditions, and represents a classic example of improper input validation in parsing operations. From an attacker's perspective, this flaw maps to ATT&CK technique T1059.007 for application execution and T1499.004 for network denial of service, as it enables remote code execution through application crash conditions. Organizations using Wireshark for network traffic analysis, security monitoring, or forensic investigations should prioritize immediate patching of affected systems. The recommended mitigation involves upgrading to Wireshark versions 1.12.12 or 2.0.4 and later, which contain the necessary fixes to properly handle unsigned integer processing in the sscanf operations. Additionally, network administrators should implement strict file access controls and consider sandboxing mechanisms when processing untrusted packet capture files to minimize potential exploitation risks.