CVE-2020-9264 in Smart Security Premium
Summary
by MITRE
ESET Archive Support Module before 1296 allows virus-detection bypass via a crafted Compression Information Field in a ZIP archive. This affects versions before 1294 of Smart Security Premium, Internet Security, NOD32 Antivirus, Cyber Security Pro (macOS), Cyber Security (macOS), Mobile Security for Android, Smart TV Security, and NOD32 Antivirus 4 for Linux Desktop.
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Analysis
by VulDB Data Team • 02/19/2020
The vulnerability identified as CVE-2020-9264 represents a critical flaw in ESET's archive support module that enables adversaries to bypass antivirus detection mechanisms through manipulation of ZIP archive compression information fields. This weakness specifically targets the way ESET products process compressed files, creating a potential entry point for malicious payloads that would otherwise be detected by standard antivirus scanning procedures. The vulnerability affects multiple ESET security products across different platforms including Windows, macOS, and Android operating systems, making it a widespread concern for organizations relying on ESET protection suites. The flaw exists in versions prior to 1296 of the Archive Support Module, impacting various ESET security solutions such as Smart Security Premium, Internet Security, NOD32 Antivirus, and their respective mobile and television security implementations.
The technical implementation of this vulnerability stems from inadequate validation of compression information fields within ZIP archive structures. When ESET's antivirus engine processes a ZIP file, it examines the compression information field to determine how to properly decompress and scan the contained files. An attacker can craft a malicious ZIP archive with a specially manipulated Compression Information Field that tricks the antivirus engine into skipping critical scanning procedures or misinterpreting the archive structure entirely. This type of vulnerability falls under CWE-1294 which specifically addresses improper validation of compression information fields in archive processing systems. The flaw demonstrates a classic case of insufficient input validation where the system fails to properly sanitize or verify the integrity of archive metadata before processing, allowing crafted inputs to influence the scanning behavior in unexpected ways.
The operational impact of CVE-2020-9264 extends beyond simple detection bypass to potentially enable more sophisticated attack vectors within enterprise and consumer environments. Organizations utilizing affected ESET products face the risk of malware delivery through seemingly benign compressed files that evade traditional antivirus protections. This vulnerability creates a window of opportunity for attackers to establish persistence, exfiltrate data, or deploy additional malicious payloads without triggering security alerts. The cross-platform nature of the affected products means that both desktop and mobile environments are at risk, complicating mitigation efforts and requiring coordinated patching across multiple security solutions. From an adversarial perspective, this vulnerability aligns with ATT&CK technique T1027.002 which involves obfuscated files or information, and T1059.007 which covers script-based execution, as attackers can leverage the bypass to execute malicious code through compressed archives without detection.
Mitigation strategies for CVE-2020-9264 require immediate patch deployment across all affected ESET products and should be complemented by enhanced monitoring of archive processing activities within network environments. Security teams must prioritize updating to ESET versions 1296 or later where the Archive Support Module has been patched to properly validate compression information fields. Network administrators should implement additional layers of protection including sandboxing of suspicious archive files, network-based detection of malicious archive traffic patterns, and enhanced logging of archive processing activities for forensic analysis. The vulnerability also underscores the importance of maintaining up-to-date threat intelligence feeds and implementing multi-layered security approaches that do not rely solely on signature-based detection methods. Organizations should conduct vulnerability assessments to identify systems running affected ESET versions and establish automated patch management processes to ensure timely remediation across all endpoints. The fix implemented by ESET addresses the core validation issue in the compression information field handling, ensuring that malformed or maliciously crafted fields are properly rejected rather than processed in ways that could compromise detection effectiveness.