CVE-2008-3215 in ClamAV
Summary
by MITRE
libclamav/petite.c in ClamAV before 0.93.3 allows remote attackers to cause a denial of service via a malformed Petite file that triggers an out-of-bounds memory access. NOTE: this issue exists because of an incomplete fix for CVE-2008-2713.
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Analysis
by VulDB Data Team • 08/01/2021
The vulnerability identified as CVE-2008-3215 represents a critical denial of service weakness in the ClamAV antivirus engine's handling of Petite compressed files. This issue affects ClamAV versions prior to 0.93.3 and demonstrates the persistent nature of software security flaws that can persist even after apparent fixes have been implemented. The vulnerability specifically resides within the libclamav/petite.c component of the ClamAV codebase, which is responsible for processing Petite compressed executable files commonly used in malware distribution. The flaw manifests when the software encounters a malformed Petite file that triggers an out-of-bounds memory access condition, effectively allowing remote attackers to disrupt the normal operation of ClamAV systems through carefully crafted malicious files.
The technical implementation of this vulnerability involves improper bounds checking within the Petite file parsing logic. When ClamAV attempts to process a malformed Petite file, the parsing routine fails to adequately validate the structure and size of the compressed data, leading to memory access violations that cause the application to crash or become unresponsive. This out-of-bounds memory access occurs during the decompression and analysis phase of Petite file processing, where the software attempts to read or write data beyond the allocated memory boundaries. The incomplete fix for the previously reported CVE-2008-2713 appears to have overlooked critical edge cases in the Petite file handling code, leaving the system vulnerable to similar attack patterns. This represents a classic example of how security patches may not fully address all possible attack vectors, particularly in complex parsing routines that must handle various file format variations and malformed inputs.
The operational impact of this vulnerability extends beyond simple service disruption, as it can affect the reliability and availability of antivirus protection systems that depend on ClamAV. Organizations relying on ClamAV for malware detection and prevention may experience unexpected service interruptions when processing suspicious files, potentially leaving systems vulnerable to actual malware threats during the disruption period. The remote nature of the attack means that malicious actors can exploit this weakness without requiring physical access to the target system, making it particularly dangerous in networked environments. This vulnerability directly impacts the availability aspect of the CIA triad, as it can be leveraged to deny legitimate service to users and systems that depend on ClamAV for security operations.
The vulnerability aligns with CWE-129, which addresses insufficient bounds checking in input validation, and demonstrates characteristics consistent with the ATT&CK technique T1499.004 for network denial of service attacks. Organizations should implement immediate mitigation strategies including updating to ClamAV version 0.93.3 or later, which contains the proper fix for this issue. Additionally, network administrators should consider implementing additional layers of protection such as file type filtering and sandboxing mechanisms to prevent potentially malicious Petite files from reaching the ClamAV processing engine. The incident also highlights the importance of thorough regression testing when implementing security patches, particularly for complex parsing components that handle multiple file formats. System monitoring should be enhanced to detect unusual ClamAV process behavior or crashes that may indicate exploitation attempts, and regular security assessments should verify that all known vulnerabilities have been properly addressed in the security stack.