CVE-2012-1443 in Avast
Summary
by MITRE
The RAR file parser in ClamAV 0.96.4, Rising Antivirus 22.83.00.03, Quick Heal (aka Cat QuickHeal) 11.00, G Data AntiVirus 21, AVEngine 20101.3.0.103 in Symantec Endpoint Protection 11, Command Antivirus 5.2.11.5, Ikarus Virus Utilities T3 Command Line Scanner 1.1.97.0, Emsisoft Anti-Malware 5.1.0.1, PC Tools AntiVirus 7.0.3.5, F-Prot Antivirus 4.6.2.117, VirusBuster 13.6.151.0, Fortinet Antivirus 4.2.254.0, Antiy Labs AVL SDK 2.0.3.7, K7 AntiVirus 9.77.3565, Trend Micro HouseCall 9.120.0.1004, Kaspersky Anti-Virus 7.0.0.125, Jiangmin Antivirus 13.0.900, Antimalware Engine 1.1.6402.0 in Microsoft Security Essentials 2.0, Sophos Anti-Virus 4.61.0, NOD32 Antivirus 5795, Avira AntiVir 7.11.1.163, Norman Antivirus 6.06.12, McAfee Anti-Virus Scanning Engine 5.400.0.1158, Panda Antivirus 10.0.2.7, McAfee Gateway (formerly Webwasher) 2010.1C, Trend Micro AntiVirus 9.120.0.1004, Comodo Antivirus 7424, Bitdefender 7.2, eSafe 7.0.17.0, F-Secure Anti-Virus 9.0.16160.0, nProtect Anti-Virus 2011-01-17.01, AhnLab V3 Internet Security 2011.01.18.00, AVG Anti-Virus 10.0.0.1190, avast! Antivirus 4.8.1351.0 and 5.0.677.0, and VBA32 3.12.14.2 allows user-assisted remote attackers to bypass malware detection via a RAR file with an initial MZ character sequence. NOTE: this may later be SPLIT into multiple CVEs if additional information is published showing that the error occurred independently in different RAR parser implementations.
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Analysis
by VulDB Data Team • 04/26/2018
The vulnerability described in CVE-2012-1443 represents a critical flaw in multiple antivirus software implementations that affects how they parse RAR archive files. This issue manifests when antivirus engines encounter RAR files containing an initial MZ character sequence, which is typically associated with executable files in the DOS format. The vulnerability falls under the category of file format parsing errors and can be classified as a weakness in input validation according to CWE-20. The flaw enables attackers to craft malicious RAR files that can bypass detection mechanisms, effectively allowing malware to evade security controls.
The technical implementation of this vulnerability occurs within the RAR file parser components of various antivirus solutions, where the software incorrectly interprets or fails to properly validate the initial MZ signature present in certain RAR archives. This misinterpretation creates a condition where the antivirus engine cannot accurately determine whether the file contains malicious content or is simply a legitimate archive. The vulnerability is particularly concerning because it affects a wide range of antivirus products from different vendors, indicating a common implementation flaw in how these systems handle RAR file structures. This widespread impact suggests that the vulnerability exists at the level of common parsing libraries or shared code components used across multiple security vendors.
From an operational standpoint, this vulnerability poses significant risks to organizations relying on antivirus protection, as it allows attackers to deliver malware through seemingly benign RAR archives. The user-assisted remote attack vector means that the exploit requires some form of user interaction, such as opening or executing the malicious file, but the bypass of detection mechanisms significantly increases the likelihood of successful infection. The vulnerability can be categorized under ATT&CK technique T1059.007 for RAR archives and T1070.004 for evasion techniques, as it represents a method of avoiding detection through file format manipulation. Security professionals must consider this vulnerability when assessing their endpoint protection strategies, as it demonstrates how attackers can exploit seemingly minor parsing inconsistencies to compromise systems.
The impact of this vulnerability extends beyond individual system infections to potentially affect entire network security infrastructures, particularly in environments where multiple antivirus solutions are deployed. Organizations should prioritize updating their antivirus signatures and software versions to address this flaw, as many of the affected products were released during a period when security vendors were still developing robust RAR parsing capabilities. The vulnerability highlights the importance of thorough testing of file format parsers and the need for consistent validation across different security implementations. Mitigation strategies should include immediate patching of affected antivirus software, implementation of network-based detection for suspicious RAR files, and enhanced monitoring for unusual file execution patterns. The widespread nature of this vulnerability also underscores the need for better coordination between security vendors to identify and address common implementation flaws that could affect multiple products simultaneously.