CVE-2012-1441 in Prevx
Summary
by MITRE
The Microsoft EXE file parser in eSafe 7.0.17.0 and Prevx 3.0 allows remote attackers to bypass malware detection via an EXE file with a modified value in any of several e_ fields. NOTE: this may later be SPLIT into multiple CVEs if additional information is published showing that the error occurred independently in different EXE parser implementations.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 02/16/2019
The vulnerability identified as CVE-2012-1441 represents a critical flaw in the executable file parsing mechanisms of two popular anti-malware solutions, eSafe 7.0.17.0 and Prevx 3.0. This issue stems from the way these security applications process EXE file headers, specifically targeting the e_ fields within the DOS header structure that are commonly used for file identification and validation purposes. The vulnerability exploits a fundamental weakness in the malware detection logic that allows attackers to manipulate these fields without triggering proper security alerts. The e_ fields in EXE files serve as metadata indicators that help security software identify and classify executable files, making them crucial components in the detection and prevention of malicious software. When these fields are modified in a specific manner, the affected security applications fail to properly validate the file structure and subsequently classify the executable as benign, despite containing malicious code.
The technical implementation of this vulnerability involves the manipulation of the e_ fields within the EXE file format, which are typically used to store information about the file's expected behavior and structure. These fields include e_magic, e_cblp, e_cp, e_crlc, e_cparhdr, e_minalloc, e_maxalloc, e_ss, e_sp, e_csum, e_ip, e_cs, e_lfarlc, e_ovno, e_res, e_oemid, e_oeminfo, and e_res2. Attackers can modify these values to bypass signature-based detection mechanisms and heuristic analysis routines that rely on proper EXE header validation. The flaw essentially creates a false positive scenario where the security software incorrectly interprets the modified EXE file as a legitimate executable, allowing the malicious payload to execute without detection. This vulnerability directly relates to CWE-119, which addresses weaknesses in the protection of memory, and CWE-254, which covers security weaknesses in the design of the system. The issue demonstrates a classic example of a bypass vulnerability where the security controls are circumvented through manipulation of input validation mechanisms.
The operational impact of CVE-2012-1441 is significant as it effectively neutralizes the protective capabilities of the affected security applications against specific types of malware. When exploited, this vulnerability allows attackers to deliver malicious executables that would normally be detected and blocked by the security software, creating a false sense of security for users. The vulnerability affects organizations that rely on eSafe and Prevx for malware protection, potentially exposing their systems to various threats including trojans, rootkits, and other malicious software that can exploit this bypass mechanism. The implications extend beyond individual user systems to enterprise environments where these security solutions might be deployed across multiple endpoints, creating a potential attack vector that could compromise entire networks. This vulnerability also demonstrates the importance of proper input validation and the potential for seemingly minor flaws in file parsing logic to create significant security weaknesses. According to ATT&CK framework, this vulnerability aligns with technique T1059.001 for execution through command and scripting interpreter and T1070.004 for indicator removal on host, as attackers could potentially use this bypass to establish persistence and avoid detection. The vulnerability's potential for splitting into multiple CVEs indicates that similar flaws might exist in other EXE parser implementations, suggesting a broader issue within the anti-malware industry's approach to file validation.
The mitigation strategies for CVE-2012-1441 involve immediate updates to the affected security software versions, ensuring that vendors have patched the EXE parsing logic to properly validate the e_ fields. System administrators should implement additional layers of security including behavioral analysis, network monitoring, and signature updates to compensate for the vulnerability during the patching process. Organizations should also consider implementing network-based intrusion detection systems that can identify suspicious network traffic patterns associated with known malware delivery methods. The vulnerability highlights the necessity of maintaining current security software versions and implementing comprehensive security testing procedures that include validation of file parsing mechanisms. Additionally, security professionals should conduct regular vulnerability assessments to identify similar weaknesses in other security solutions and ensure that proper input validation is implemented across all security components. The affected software vendors should have implemented proper input sanitization and validation routines to ensure that modified EXE headers are properly detected and rejected as potentially malicious. This vulnerability serves as a reminder of the critical importance of robust input validation and the potential consequences of incomplete file format parsing in security applications.